Species endangered (MS-Blog Series from) VII / 09

Minke Whale

Class: Mammal

Order: Cetacean

Latin name: Balaenoptera acutorostrata / (and)
B. bonaerensis

Range: North Atlantic; N. Pacific (Pacific) / Pacific; Antarctic Seas

IUCN Status: LC (Least Concern) / DD (Data Deficient)

Cites: Appendix I

(probably) 2008 situation.

Having reached whales in our expedition from the endangered species, a few words are prerequisite from the following posts in the series. Since us, like humans usually, probably by instinct feel closeness to mammals as the most 'human-like' species from all the animals, larger part of our examples so far has been focused on them. For all the fairness sake, and because there's (yet) only one from birds, amphibians, [and/or insects], and not one (yet) from fish, either from the less 'defined' cases (marine invertebrates, et similar perhaps), likely we'll in the following posts include more some those 'strange and more distinct from us' (at least seen from evolutionary perspective). However, the couple remaining mammalian examples are presented before that(of course there would be many likewise worth including, but our reserves are rather limited and so these selections only represent individual choices.)

Whales nowadays include many endangered species, that being a direct result from the long history of hunting them by man. Also, as result they have much become a symbol from the overuse of the Oceans rich variety of life. Alternative choices here could have been, if wished - and only from baleen whales like Minke – any of the more endangered ones, well-known species like fx Blue whale (B. musculus, EN), Fin whale (Baleanoptera physalus, EN), North Atlantic Right Whale (Eubalaena glacialis, EN). And/or, such like Greenland whale/Bowhead (Balaena mysticetus, VU) and Humpback (LC) that are sometimes mentioned as successful examples from conservation efforts, only make one also reminded from that their recently found 'renewal' may equally be seen as consequence from early date of these species becoming protected (Bowhead as early as in 1930s. Also was in 1930s protected fx the North Atlantic Right Whale, however it's eastern Atlantic population had probably been extinct until that because of whaling. In any case, both species were hunted to low numbers even before spread of the 20^th century commercial whaling techniques, for the reason that they were relatively 'catchable' with more traditional methods. So, the protection was as much the result of these species catches having largely collapsed until the decade.)

The Minke whales we are presenting here as our main subject, (though, these series more or less discuss also other related things/species), were just in the 1990s decided to be consisting two differing species, the arctic and antarctic Minke whales. Species earlier other common name, Lesser Rorqual (more archaic term, it's about synonyme for baleen whale, so it quite describes the species) as they only regularly weight some 5-10 tons (maximum about some 14 tons), which can be compared to Sei whales(EN), third largest from Baleanopteridae that can weight as much as 20-40 tons. Minkes are the second smallest from baleen whales. Like the baleen whales usually Minkes eat large amounts of plankton, but also in various scale fishes, even the octopuses on warmer seas. Their range consist all of the Oceans, the main populations being found on North Atlantic and North Pacific. (Occasionally the individual whales get lost from the more unusual ranges, Minke whales have few times appeared on the Baltic Sea, and also in the 1980s one specimen was found having landed on the bank of Amazon river about 150 km inland the river !) In the southern ranges Minke whale populations are less clearly recognized, partly from difficulty in dividing between the mentioned (co-)species (.acurostrata/.bonaerensis). These whales are estimated to live about 30-50 years, exceptionally even for 60 years age. The gestation period takes about 10-11 months and may occur about in every second year. Also, they tend to have more efficient reproductive probability than the larger whale species usually do.

Comparing to those other whale species mentioned before, Minke Whale may not appear to seem as much threatened. It's not only second smallest from baleen whales, but also the most common one and probably was even before the whaling times. In fact, by any logical reasoning one notices it shouldn't even have become endangered at all if that could have been on the basis of any typical/regular human use of natures resources. More likely, one could expect it to appear as common as the most populous from sharks or comparable in abundance to some widespread terrestrial animals, that in many regions remain rather common, fx moose or rabbits, perhaps. But, whales being large slowly reproducing species even the Minke whales became chased for decline in short time during the latter part of 20^th century commercial whaling. After all, the prolonged period of that over-hunt, starting from the first decades of the century with the invention of exploding harpoons and factory ships continued up to the 1980s – At that point it had to end even on the basis of commercial reasons; the hunt having annihilated largest parts of whale populations from the seas. Also noticeable, the collapses in the catch of particular species repeatedly followed quite parallel with the whalers changing for the next species being hunted extensively (Once the Blue whales were out-whaled, Fin whales populations were next collapsed with the same logic, then Sei whales, and finally even the Minke Whales were taken in use of the whaling market, although they had on preceding periods of hunt been overlooked, since there still was enough larger whales left to take benefit from.)In during this period of time (known from statistics is ca 1930-1980s) also the average weights of the catched whales collapsed: from ca 50 tons in 1930s for 10 tons in 1980 (though the latter number is largely from the reason Minke whales at the time consisted larger part of catch, but the course ,it can be noticed, was all the way same thoughout the decades).

Traditional whaling originates for the early history (fx hand-harpooning at the Norwegian coasts is known from about 9^th century and from Japan at least from the 12^th century), probably it's been practiced (elsewhere too) from as long as other larger animals of the seas have been harvested for their meat. Commercial market and products made from whales also has longer histories. Its origins are perhaps in the 16/17^th century, although the techniques were developed slowly, but at first also the stress it caused on whale populations was limited compared to later times. Fx, if we are to trust supposed time-gap presented in this brief description from formation of one from most famous whaling centers, Nantucket, it took almost 100 years(from 1660-1760) for the earliest market to demolish the Right whale populations from the waters close to that early (whaling) center – And as the catches were relatively numerous in some years it seems also to support estimates that probably preceding this early beginnings the whales on seas were considerably more numerous than often is estimated on basis of the populations still left in the 20^th century. Following the earliest years of whaling, use of boats later changed for longer trips carried on ships.

Profitable businesses more usually appears harmful and rarely beneficial for any animal species, but in the case of whales hunt was at least in the 19^th century based on uses of several products that could be gained from whales in large amounts; whale oil, had been preferred as source for the heating and lighting already since 12^th century when the Basques begun the (whale) market. Also the whale bones have had various uses, fx for piano keyboards. Later, Sperm oil and spermaceti were gained from Sperm whales heads were used in fx cosmetics and lubricant, as well as the ambergris,from the same species and also used in production of perfumes(ironically it could have also been collected easily from the plentiful amounts released by whales and floating to the coastal sites). However, these early commercial uses were gone and replaced with alternative materials by the end of 19^th century and in during the early 20^th century expansion of whaling and commercial market almost only (sole) main product that drove the hunt was whales meat – and so, mostly it went for the uses of human foods, restaurants and canned products (much like tuna fish today), and, for the pet foods. Business generally was then finally stopped in the end of 1980's (though not including the limited catch some countries still maintain for 'scientific purposes' – as that's the usually applied terminology for it). But, in this context we're not presenting more exact histories of commercial whaling since one can fx read more from that in Farley Mowat's Sea of Slaughter (1984) (- the book also tells fx from origins of the whaling, as well fx Spitsbergen, and also from the history of other sea species largely overhunted at arctic/northern seas.) Of course, nowadays that whales are more widely seen as species need of protection (than in the past) there's variety of other books from them, and also from the whaling history preceding the whaling moratorium announced in late 1980s.

In spite of the temporary halt from about the 1987 to the early 1990s the whaling of Minke whales was resumed at 1993, though somewhat limited in numbers if compared to earlier periods. Anyway, at least Japan, Norway and Iceland have continued hunting them until recent times (fx on the basis of mentioned 'scientific' smokescreen). The Minke whales, (Minke populations, Wikipedia 21.8.09) are nowadays around 100 000 in the northeastern Atlantic and considerable more numerous in southern hemisphere. The human caused reduction in their numbers mainly was a result from the hunt only since 1970s - in the 1980s it was estimated that there was about 80 per cent still left from the original populations, which, again can be compared to less than 10 per cent survival margins that at the time was estimated left from some of the larger species, like Blue, Humpback and the Greenland whales. Also, the populations of Sperm whales and Gray whales (Eschrichtius robustus, LC) fx were at the time found severely harmed and remain so (Gray whales are usually considered not as threatened largely for the reason that the West pacific/Californian coast population has been found having recovered for some time now). On the basis of precedingly noticed it's also not surprising if it being that species(Gray whale) Atlantic populations had been extinct - with most probability was, and likely proven by current researches - already in the 18th century.

The Antartica as whaling region wasn't at any amount comparable targeted by whaling until the 20th century. The mentioned abundance of Minke species on the antarctic seas has sometimes also been supposed a result from unbalance in the regions (antarcticas) ecology, the populations of whales species having declined more severely and some other species having found increased correspondingly in number, that perhaps also slowing the re-emergence of the larger whale species. As whales eat large amounts of krill, the declined number in the larger ones may have caused amounts of these sources of food having become increasingly available to other species which were found increasing more effectively (like Minkes, but also penguins and seals). As well also human fisheries collect of krill likely affects for that (krill a source of commercial use too). Nowadays of course, other environmental changes noticed on antarctic are more often mentioned.

In addition to the past effects of commercial whaling briefly described in the preceding paragraphs, the Minke whales are nowadays subject to incidental catch on fishing gears, although thats not usually assumed as significant threat on them as whole. Other mentioned threats are mostly found in form of the marine pollution - also, in the same instance one can notice that there's also various pollutants gathered on whale meat (though supposedly that's comparable to some largely fished and eaten species that also gather toxins from their smaller prey, salmon and tuna fish, fx) - not to mention the other junk released to the oceans, marine debris, ao. Over-fishing also is considered as one factor that may affect the whales recovery for the worse.

From the many connections in between man and whales we didn't quite find anything especially from the Minke whales, but fx from dolphins there's plenty famous stories that can be mentioned in this connection; in ancient greek legends the dolphins were often respected animals. Also, Aristotle (384 BC – 322 BC) who was perhaps earliest natural historian, knew dolphins well. In his writings they are correctly described as mammals and also mentioned capable hearing underwater voices. Likewise, it can be mentioned some dolphins in the aquariums having been taught to understand number of words. And, as is the case that also other whales, not just the dolphins, use sonar for transmitting the messages to each other under waters, it's likely that these species have more sophisticated ways to communicate that even today is known. This has been, also perhaps one of the reasons they've gained in popularity and the whale tourism become favorite hobby (nowadays one can even adopt a whale, as is advertised on the Whale and Dolphin Conservation Society page) - By the way, the pages also contain an interactive map from whale populations on Oceans of the world. But intelligent animals as the whales are, probably they still also hold some surprises that have not yet been revealed for the humans.

In the final paragraph, one can then of course speculate from where this earlier fanatic willingness to annihilate these sea giants might have originated/grown from (Already at Moby Dick, 1851, a popular novel written at the time of early whaling, Herman Melville (1819-1891) in his often cited sentences presents expectations that the (Sperm) whale likely wouldn't last very long such an intensive hunt. However, they did until our times, largely from the reason that the whaling after turn of the century merely focused on other species, only later since about half 20th century it returned also on Sperm whales, more intensified than ever before.) An often presented (/psychological reason) interpretation states that in the past human history the Oceans were often feared and indeed found as dangerous places, that having resulted for human 'revengeful' behavior towards them and the whales. That's of course rather controversial view, and anyway, I only find it secondary explanation. More likely, it seems to me, the whole of it just tells from how the profits gained from seas easily did overdrove any other reasonable points-of-view (since it was merely understood that they were there for the taking, consequences from the practice given less thought for or cared from). In principle, at the beginning the whales in their large numbers available likely offered a relatively easy way to make money from trade and perhaps also it appeared as an suitable way to generate also other trade in the coastal towns and people. From todays perspective of course, it only seems surprising that such business wouldn't stop any time earlier (and that last century overexploitation of resources and whales was still in scale and techniques not comparable to any of the overuse seen before).

(G.U.J.)

[This post in our series has dated information as well as not completely verified data, and also contains personal opinions, so the views presented aren't necessary those shared by all participants from us. However, we do share the view that complete whaling moratorium should remain and stay in effect for another 20 years to guarantee the adequate recovery of populations.]

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Muleskinner book Recommendation #20

Mammoths, Sabertooths and Hominids:
65 Million Years of Mammalian Evolution in Europe

(Agustí, Jordi / Antón, Mauricio)

p. 2002 (N.Y.), 313 pages [+ 16 Color illustration plates]

[Recommendation 10/2009]

Anyone, having followed our recent series here (even in a haphazard way), might have noticed we've repeatedly referred for this book. Not surprising, since we've also recently a lot focused on topics of animal prehistories and distant evolutionary pasts. This actually has been, perhaps from two reasons:

First is simply because of Mammoths, Sabertooths and Hominids is very good introduction to those things, concerning (mostly) those millions and millions of years before species named sapiens(es) ever walked on Earth. And like the subtitle says, book covers mammalian evolution from Paleocene period (ca 65-55 Million years ago) to the most recent epoch preceding current times, the Pleistocene (about 1.8 Ma to 10000 BC) - actually the subtitle more correctly gives impression from books contents than the well-known species mentioned in main title. The book takes in closer examination vast number of those foregone creatures, most of them from more distant origins.

The second mentioned reason is equally meaningful (for myself). It is from the reason(/must confess that) in schools having skipped the course about the mentioned subject. So, therefore I've found myself desperately in need to fill some 'blackouts' on my knowledge from this field of study. And, as it being so I never finished the course, I'm often in these text borrowing a bit from more peculiar sources that are loosely connected characters in the archeologic history and past, early architect-archeologist's or similar innovators of the study – fx some famous ones like Frederick Bligh Bond (1864-1945) and Sarah Winchester (1839-1922). But returning to the recommendation here, this book is only presented here as an example from more modern (/more recent) researches and readings. (And, I'll also have to add that likely our aim to focus on female authors in these subsequent posts will now have to be delayed for a little further.)

The book may be in use as course-book or additional reading at universities, and as such it's not perhaps the first text to start from, if looking to read from the 'evolutionary roads' preceding the present environments and ecology. But it's not too complicated or difficult if having some basic knowledge from the earlier prehistoric periods. And they mention in the forewords its main purposes being fx offering a presentation from mammalian evolution (in Europe) for wide range of readers; from geologists to students, scholars, etc. As it focuses on study of the fossil fauna, things are presented rather chronologically, an aspect that also makes it somewhat easier to follow, if sometimes little boresome from the unprofessional readers view-point.

But, like said, it is still very recommendable as presenting a carefully structured picture from the prehistoric animal evolution (mammalians especially, of course). In overall also fx what is known from the climates in during past geologic periods. Perhaps the more recent techniques/molecular studies isn't that much covered in the book, but as I kind of remember having read the DNA discriminated from fossilized bone giving reliable clues only somewhat a million years to the past, this is only logical. Also the classification of those ancient species, especially nowadays foregone genera, isn't at all clear in every case, and the information of course sometimes changes in times with further studies. But I guess this must present quite much the most recent knowledge and foundings (mainly) on the basis of these 'traditional' research methods.

The larger parts are devoted to the earlier (faunal) periods in the prehistory - Paleocene, Eocene, Oligocene, Miocene, Pliocene. Also, the reader finds major part of pages dedicated for the more distant periods than the ones closer to our times. This is also only logical, and quite as well underlines how recent actually is the age of man - and - how much more further reaches the history of most other creatures of the Earth (and the book only concerns youngest of animal orders, the mammals).

Not even trying to describe any of those periods discussed in the book with more detail, we're only mentioning here some things that were most of interest to us. Of course described are the evolutionary paths in behind of the current existing species, like the origins/lineages of Perissodactyls, Artiodactyls, various carnivorous mammal genera, and, as well fx the Lagomorphs (rabbits/hares) and Rodents. As well, one also learns quite an amount of information from many lineages that once existed, but now are known only from fossil remains: fx Multituberculates, Machairodonts, Chalicotheres, Creodonts – An interested reader can of course read a quite deal from them also in the net, though not explained as much with detail and throrough way. Going the further for the past, the less clear/sometimes differing in views are also these classifications concerning the (groups of) species, like in the case of the latter mentioned (Creodonts), as is described here (the post also has pic from painting that funnily 'jokes' on this question). Of course, one has first to be somewhat interested from all those foregone times to enjoy the book largely focusing on explaining the changes of individual species and mammalian families during the path of some 60 million years evolutionary diversification.

But, then in the book are also mentioned some interesting 'zoo geographic problems' and geologic effects that has been able to show having happened in the past and had their affluence on all these things. I only mention here some briefly since they aroused interest in myself : The presence of Eurotamandua in Eocene faunas (of Europe), supposedly resulting from the existence of Iberian-African corridor in the Mid-Eocene ; the sudden appearance (from out of nowhere) of the early Chiroptera (bats), in the early Eocene ; the “Gomphoterian land-bridge” (early Miocene). And, other things that one is most delighted to read from, if having some interest on these distant times. Exciting especially since all of it predates so far in the past, and yet can still be reasoned and studied in our times.

Finally, we'll only mentioning the book being only better from the many good drawings (by an artist M.Antón). Like usually is the case in this kind book from specialized field – where the readers (us at least) aren't much in beforehand knowledge about presented things – they offer an easy informative view for those many odd and distant species that would be more difficult to imagine otherways. (Even, if we remember any of that being based on assumed looks and reasoned conclusions, mostly on the basis of excavated skeletal record). So, I must say, it was very useful book to read, even if I'm not much familiar with any relevant examples/comparable presentations from these subjects. Perhaps its also so, that I found the book such inspiring 'cause it mainly concerns the lesser generally known and more distant (evolutionary) times than the usually popularized imaginery from the prehistory. Although - if we in the future select some anthropology or prehistoric research to our series - them will probably be concerned on more recent periods.

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Cooking Companion IV

...fROM The gARDEN Of eARTHLY dELIGHTS...

It being harvest time, August, and so our Cooking companion this time utilizes vegetable that is not only easy to cultivate but also very high-yielding, the Squash (- I guess that's the english name, the particular pumpkin I mean one can see from pics of this post). Our favourite choice in the home-gardening, though one needs to make suitable growing soil and also they need plentiful sunlight. Otherways, it's not too demanding and I noticed this year the flowers are also beautiful, even though they only blossom a short time, some hours perhaps. Also, some of the flowers(ones that don't grow straight from the fruit) can be prepared for to eat.

These are easy made home cooking recipes, and one can of course invent more of them from ones own imagination. From the better known ones Ratatouille is perhaps the best recipe in which some squash should be used. As I like to eat it in this time of year with all kinds of meals, I often make ratatouille for an additional serving, only that I rarely remember to make lots of it to prepare some to be kept in freezer and eaten later. (W.-G.)

Sliced baked pieces

Ingredients: 1-2 Squash (yellow/green - doesn't matter in any of recipes although I sometimes think yellow tastes a little more sweeter, but I really don't know if thats just a feeling), olive oil, garlic, curry, black pepper, (white vinegar),(feta cheese)

Slice the squash alongside for suitable pieces. Then pour some 2-3 spoons of oil on pan (add that according to need), add a garlic glove(s) and perhaps some white vinegar. Let be for some 3-5 mins, turn around them a little, add spices and also add some feta over each. Fry for some minutes more and they're ready to serve.

Soup

Ingredients: 1-2 medium Squash, 1-2 dl cream, white pepper, ¼ tsp salt, vegetable oil/butter, 1 small onion, 3 dl-0,5 L water/vegetable broth, (add other spieces acc. To taste)

First slice squash(es) for small pieces, then keep them in butter/oil at kettle for a few minutes. Add broth and onion crushs + other favored spices and bake for about 10 mins. Finally smash the contents in the kettle and pour along the cream. Heat, add also pepper if wish. Offer with some bread and/or with other veggie delicatessen.

Pizza

Ingredients: 1-1 1/2 medium squash, various other vegetables (I used broccoli & pepper slices), (black) olives, tomato crush, salt, olive oil, grated cheese, some honey, (+other spices one wish to add)

This one prepares easily if you first have made a dough for pizza ready. Then just cook in the kettle some oil, crushed tomato's, add little salt(soya, perhaps), honey and spices. One's coollen a little, pour sauce over the pizzas you have made for rounded pieces. Add lengthwise sliced squashes, pepper, and small rounded broccoli pieces. Olives and grated cheese finally and then I also added some spoonful of olive oil to make it even more tasty. 250 C and some 15 min. (Can well be eaten coollen as well, but I think its better straight from the oven).

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And, since we don't want pretend being vegetarians...I guess we'll then make the subsequent recipes (whenever they're posted) from fish, chicken and something not yet decided (not the beef anyway, but that's just for the reason that I find most of the sold meals and products tasting every imaginable way inferior to the well-prepared, freely grown stuff. Not to mention the Mad-Cow, Carsinogens and other various by-products like animal diseases, but that's another story.).

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Oh God! It's raining technologies...

: MulSkinner [Hi-]Techs be-bop-a-lula : IV/2009 (Late summer)

Like goes the phrase - don't know how spells the quite correct alternative for it in english - but I guess kind like 'What goes around, goes around', as usually is the case. However - not the least - that we've been so much stressed with all these projects, but especially from the reason that our most recent effort to execute this tech review only left us bored and frustrated from MSW tactics in general, we've not much bothered to follow all the latest tricks and chipmunks from the advancing hi-tech fields.

So, we're really not much this time waving the flag for advanceful or even greenery technologies; actually we've not even checked the recent(?) Green electronics briefing from Greenpeace this time (As well, unchecked goes also the F-secure cybersecurity reports Q2/09 and we'll only noticing that surprisingly Adobe's files were gaining a lead from Word-docs as the most vulnerable and most targeted with attacks – Oh, save that good old Pdf-reader with necessary fixes and replacements, soon.) - And as consequence from all this, this tech review now goes purely by guessing...

From the news, about dot-Eco-com we only hear those inspiring words '.eco should mean something more than just another domain.'(T.B. as cited on BBC-news), but I guess the question must have been solved years ago and there now should be plenty more than only few domains devoted and labeled with the "-".eco. As well...The long-awaited Win 7 wasn't yet available here, but we noticed it's rise and shine in the gleaming outer looks of some other software's...Equally as well, from the recent trends we can only guess that the Ipods were still (occasionally) bursting on flames but steadily selling like hell. Likely, the big consumer question was re-emerging in form of Microsoft's contender for the device, Zune HD, costing probably not so remarkable sums anymore - the largest, 32 Gb model was presented to us buyable with some hundreds of $'s – I guess that much storage capacity is a minimum needed for all these new space-consuming film and media files...But hey: they say the improved Pod will even have camera(?). Who really needs a camera-Pod in these days of miracle and wonder, long-distance-net-calls , camera- and music-phones altogether? ...But perhaps we're just envious in our newly found enthusiasm from the players, even sold without entertainment taxes. However, like an answer to our prayers for futuristic storage space needs comes the news from this Kingston 256 Gb-Tiny Tardis USB-drive, which goes easily for pocket and with the more advanced technologies could serve as re-changeable storage in those more forward-looking devices cleaning the table from competing copied players, etc., ...Only that the price is too astro-physical to even be mentioned here, but in time - and if our predictions are to be trusted and correct -, by some five years it should cost less than the cheap MP3-players these days do (rough guessing some 80 per cent price cut in 7-8 years)

...And as well handheld business was probably (we guess) growing on steadily and more steadily in spite of the already passed roadside warning 'oversupply on the market' (and also we noticed emerging new fields expected fx in form of the arrival of Nokia 2720-30/7020 models, targeted for growing consumer markets of the developing world, especially for the users of mobile email, etc). From the more front-end phones we were introduced to the wonders of Samsung GT-S5230 that has qualities starting from fx the 3.0 WQVGA touchwiz LCD and (programmable?) add-ons for the services/net. Seems quite a recommendable choice and probably usable for realistic period of time (but perhaps we'll consider taking a closer look for it in the separate post...)

Other things we in passing noticed were from less Earthly aspects; Concerning our slight interests on A.I.'s emergences and even in knowing the Roszak's (The Cult of Information) early warnings from the prophecies and foresees presented on this field time to time, it's actually advertised being closer than we expected, as they say “It is not impossible to build a human brain and we can do it in ten years.” (IBM blue gene machineries etc involved makes me little suspicious on the expectable horizons from this project...), but they also mention it could fx have use to finding treatments for the mental illnesses and their supposing it will even be capable to answer the questions...what a gift from gods...Is there a thing human brain couldn't invent...From completely another field of inventions, on the cyberworldly affairs we find equally non-material existence of the flash-cookies (Local Shared Object - LSO), which they claim to retain those little information bugs, even if having been destroyed by user...however, it isn't even illegal, surprisingly, but who would be/is the first offering a browser to erase those tiny little monsters...And then there's even more advanced fields of physics and high-techs, namely “Hidden portal concept: First tunable electromagnetic gateway” (if I understood the concept correctly it yet only means something similar as the artificial invisibility techniques we noticed in the Newspost(17-08-2008) almost year ago/or the invisibility cloak of the Potteresque universe and novels, although they've got the nerve to loan in the headliner a comparison to the teleportative entrance to School of wizards in Potters...Anyway, or about so, as I interpreted this oncoming direction of modern physics from those sentences;) “[the Gateway]...uses transformation optics and an amplified scattering effect from an arrangement of ferrite materials called single-crystal yttrium-iron-garnet that force light and other forms of electromagnetic radiation in complicated directions to create a hidden portal.” - But go and read the newsies in question at ScienceNews, or for further information check the link to complete article published on New Journal of Physics...it's only a few pages. I guess one don't need to imagine possible commercial uses and profitable markets in this instance, but it also kind of reminded me of and from the Hyperion/Endymion (1989-1997) series of novels by Dan Simmons where people are using Far caster-transporters, River Tethys flowing uninterrupted through those ports (but it's some time I've read the book and it's quite a complex invention to describe even in form of it presented at those scifi books).

Finally, and as entertainment ease for our otherways heavily techs and physics oriented briefing we have some information from worlds most entertaining ape, Cheeta (that being a correct spelling, I noticed): 'The character was actually a composite role created by use of numerous animal actors'...what? Isn't the one and only Cheeta the one and only? ...No, but notably devastating is that this variety of chimpanzees playing the character isn't (surprisingly) reflected in the fictional autobiography Me Cheeta (2008) that claims to be authored by only one chimp also acting the role in all the films as well. Since preceding information sounds highly controversial and offers opposite claims, we ourselves recommend - at least for the reputation of that remarkable actor - it being cleared up that the directors didn't use doubles, triples or even couples in the movies (obviously, there can be only one Award-winning Cheeta).

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Prelude, August 10.8.2009

In the days of the August, we're not quite at the end of summer yet. However, in some sense this makes it closer to the end of certain period on this blogs wrtitings. So without too many words, we're preparing for the future with this little funny post, a prelude as we've named it this time.

Like has been our usual manner, including a disc recommendation under the pretext of this. Without questioning, it's QuickSilver Messenger Service and Happy Trails LP from 1968. There's several classics worth the mention; Mona, Who do You love (-Suite, makes the whole of side A). And Cavalry...And I even close my eyes and imagine those days of fantastique and nostalgics; '...Rhett Butler galloping in front of the Blue coats with his white pony, on a way to pick up Scarlet O'Hara from her residence of withdrawal and remorse ...or Johnny Weissmuller riding his herd of elephants, Maureen O'Sullivan lazying on the back of another, Cheetah giggling ...And then I think about John Carter and hope to be absorbed for the Mars through space miles like he did and ended riding on a Banthan(I guess that's the correct spelling/name of the species?...), Dejah Thoris, her red hair flowing from the distant winds, and that Gigantic Thark with his four-hands and those impressive canine tooths...'

...But it also goes without mentioning that the disc also contains some of the greatest guitar sounds ever recorded (besides, the cover is also great...)'

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Species endangered (MS-Blog series from) VI / 09

Hawksbill Turtle

• Class: Reptiles
• Order: Cheloniidae
• Latin name: Eretmochelys imbricata
• Range: Atlantic, Pacific and Indian Oceans ; Shallow tropical/subtropical seas, coral reefs, mangrove bays and estuaries
• IUCN Status: CR (Critically Endangered) / Cites: Appendix I

(2009 situation).

All from the living Sea turtles are counted among the oldest of currently existing animals, since earliest known ancestors for them are believed to have distinct from other turtles at least 110 Million years before our times. Likewise comparable to length of that evolutionary history is the species relatively long life-ages; an individual sea turtle can live up to 80 years, in natural circumstances.

Hawksbills 'justified' 'qualify' among the most threatened of sea animals and the level of endangerment isn't much differing in case of the other existing marine turtles. In fact all are threatened from their main surviving family Cheloniidae - that means; Green turtle (Chelonia mydas, EN), Loggerhead sea turtle (Caretta caretta, EN), Kemp's Ridley (Lepidochelys kempii, CR), Olive Ridley (Lepidochelys olivacea, VU) – the Flatback Turtle (Natator depressus), endemic for 'seas closer Australian continental shelf'' is listed as DD (data deficient). Another family of sea turtles, more evolutionary distant Dermochelyidae, includes as its sole surviving member only (equally Critically Endangered) Leatherback turtle (Dermochelys coriacea) - The largest from sea turtles, as individual specimen are known to have weighed from 250 kg to almost 1000 kg. (But smaller sea turtle species regularly weight under about 50 kg. To the comparison one can see the estimated size of turtles from Leatherback's extinct co-family, Protostegidae, which included fx Achelon, largest marine turtle and only found from fossil remains – although according to current knowledge they (perhaps) existed in the period of sea turtles early evolutionary beginnings, closely 100 Million years in the past.)

The sea turtle populations are only known by estimates, since they can be only counted from the turtles that come ashore to leave the eggs on breeding seasons(female specimen). As the Hawksbills are widely scattered around the oceans of the world, their nesting sites include sites on the coastlines of at least 58 countries. As turtles often, they are slow breeding reptiles (Hawksbill Turtles reach maturity not until 30 years age). A single turtle can leave about 140 eggs on one clutch in their breeding time, but from that number only few if any reach the maturity age. In addition to human actions, turtles eggs and hatchlings are predated by fx monitor lizards, crabs, dogs and seabirds. The interval between the breeding periods is about 2-3 years.

Since historical times, sea turtle shells have been collected by humans for decorative purposes, like jewelery, ornaments, glasses frames (and in our more luxurious days this has led even for such products as guitars made from turtle shell, like explained on this WWF-page briefly). Although the turtle trade nowadays is prohibited, the illegal market still flourishes. As well, turtles meat (and their eggs) are still preferred food sources in some countries. Also, many of the fishing nets still are 'non-turtle safe' where they get trapped (safer ones are fx those equipped with TEDs - so called turtle excluder devices). A sea turtle has to breath on the surface, otherways it drowns, and although they can sometimes remain hours under surface when sleeping/in rest, if in movement this time gap shortens a lot, for only some minutes.

And, other threats include fx also the marine pollution (marine debris, environmental contamination, etc), erosion of sea-side lands, non-native vegetation, and the destruction of coral reefs from silting and human building purposes, artificial lighting (last mentioned is threat since new-born hatchlings by instinct go towards the brightest source of light, and very often human lights on beaches etc leads them for the opposite direction ie they don't head for the sea) - and, as well diseases like FP (fibropapillomatosis), whose formation is not completely understood (/or: here in MSW a search from its causes fx from Wikipedia didn't return much information/researches post 1995), but likely the main reason is related to human caused pollution on coastal areas. (For more information see fx Aguirre-Lutz(2004)^{Note 1.}, and the other articles found we listed in the end of this, though due the aforementioned reasons we can in this case only advice to check for more recent information as well...) Anyway, in the 1990s the disease was even feared to ultimately cause sea turtles complete extinction, but nowadays is believed that in favorable conditions they (marine turtles) can recover from the disease in question. And...(the list continues) oil spillages for the sea waters of course, which in some parts of the world (middle-East, fx) is major problem. One enlargening harmful co-factor in the recent times has been the increase of tourism, since turtle breeding sites, sandy beaches have often been taken for the use in human purposes (most recently in the tropical coastlines of Asia). Mechanical beach vehicles, even walking can trouble turtles breeding and destroy the eggs/hatchlings. As peaceful beaches have continuously become rarer, also sea turtles nesting sites have declined (in during 20th century).

The effects of global warming on them are not yet known very adequately, but coral bleaching is one consequence believed to lead for losses in their natural habitat, coral reefs. Another, supposable consequence, although yet far less known with certainty is the possible effects from the warming of sea temperatures. For the migrating species, such as the Leatherback turtles, this can possibly cause changes for their usually preferred sea and terrestrial sites. Because the sea water temperature affect for the migratory routes turtles take, it is fx feared to also complicate already difficult conservation efforts - But since that's only researched nowadays, see (fx) "As the Seas Warm" from selected texts below. Also Hawksbills are migratory and one individual turtle can make rather complex journeys during its life-span.

Also, (many) sea turtles are dependant on the seagrass mats, growing close to reefs. Seagrasses are often considered having an important role as 'ecotone' in between the reefs and mangroves growing closer the coastlines, not the least because they have potential to adapt relatively easy for impacts of climate change and offer some protection from other factors, like fx the soil erosion of coasts. However, seagrasses also face several environmental problems, ao in form of declining water quality and chemical pollution, usually caused by herbicides and pesticides originating from coastal agricultural uses.^{Note 2(p. 35-6)} (Question also has some considerable economic importance for humans since fx WWF 'The Coral Triangle"-Report notices the Climate Changes destructive impacts on coral reefs affecting some 150 Million people living in the region of Coral Triangle, about two thirds of them dependent for income coming from the biodiversity of the reefs, commercial fisheries by largest part but also some directly from fishing and from tourism as well. Also, importance of reef as biodiversity rich area is no less remarkable; the fishes, corals, etc., are mentioned appear there with greatest numbers of species worldwide.)^{Note 3(p. 36-43)} Especially concerning the particular one species here, Hawksbill turtle, sea turtles are noticed also having important part in the reefs ecosystems, since their diet often contains various small invertebrates (that somewhat varying between the different species, but includes sponges and mollusks, snails, jellyfish, crabs and seaweed, and also algae). Therefore they have their part to do in the maintenance of healthy coral reefs – fx Hawksbills in various sea areas by controlling the spread of sponges which otherwise can out-compete reef-building corals for space ^{Note 4}.

Human caused pressures for sea turtles probably originate from rather long time, but especially they have been noticed in the recent 50 years time. As result, the Hawksbills are calculated as Critically endangered, mainly because in most of their populations there likely was/is noticed 80 per cent reduction during the past three generations – earlier, until about 1970s species was listed as Endangered. (To the comparison: Supposing turtle average life span about 40 years that would mean about 120 years period. For some other threatened species like fx Cheetahs [Acononyx jubatus, EN] period for the same three generations time is a lot shorter, about 42 years. Often, the time needed for the succesfull recovery may take even more time than that and species with longer time for maturity age naturally take more time to recover from continued overhunting, etc. Of course, doesn't prevent us to mention the Cheetahs being almost as much endangered, and some subspecies are also counted as CR.)

According to estimates in during that about 100 years, some millions of individual Hawksbill turtles were slaughtered for uses of the Europe, United States and Asian markets. Nowadays, as the declining trend has been noticed for some time, the conservation actions include fx establishment of protected areas for the nesting. Also, sea turtle trade was prohibited and species listed in 1970s with Cites appendice I (from the earlier appendice II; however, a largest buyer of tortoise-shell market, Japan didn't ban the shell imports until 1993). Since the international ruling is not always considered as binding agreement in all coutnries, the illegal trade still continues in some parts of the world. And the regular fishing too, which causes large number of turtle deaths, yearly. Juvenile Hawksbill turtles have also been noticed probably more vulnerable to be harmed by fishing nets than some other sea turtles.

All these things considered it appears by no means surprising that they're endangered by most populations. The changes on human use of the seasides would greatly benefit their chances for recovery, fx reduction in the building of new beach sites and/or coastal residents. Since no-one believes that to happen, and can't expect the marine pollution to lessen either, supposedly the protected marine areas and decline in the illegal trade are their best hopes. Not until recent times there probably hasn't been much such conservation areas, similar to those on land (But because we don't claim to hold any uttermost knowledge from the subject/marine conservation, etc, reader is also adviced to view further readings from fx the links/texts selected below.)

And, as we at the moment haven't searched any suitable Hawksbill picture, can possibly finally in this post see that creature swimming in its natural habitat (video from Arkive):

Hawksbill turtle swimming in habitatwww.osfimages.com

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Notes/further reading:

Coral reefs:

[Notes 2 and 3] The Coral Triangle and Climate Change: Ecosystems, people and societies at risk. WWF. (pdf) available fx here.

Fibropapillomatosis(FP):

Herbst, Lawrence H. ; Klein, Paul.A., 1995, “Green turtle Fibropapillomatosis: Challenges to Assessing the Role of Environmental Cofactors”. Environmental Health Perpectives 103:28-30.

[Note 1] Aguirre, A. ; Lutz, P., “Marine Turtles as Sentinels of Ecosystem Health: Is Fibropapillomatosis an Indicator?” EcoHealth 1, 275–283 (2004), doi: 10.1007/s10393-004-0097-3

(summary – obtaining complete text requires payment.)

Mascarenhas, R ; Iverson, P., "Fibropapillomatosis in Stranded Green Turtles (Chelonia mydas) in Paraiba State, Northeastern Brazil: Evidence of a Brazilian Epizootic?", Marine Turtle Newsletter 120:3-6, [2008?]

Marine Turtles:

[Note 4.] Mortimer, J.A. ; Donnelly, M. 2008, Eretmochelys imbricata. IUCN. IUCN Red List of Threatened Species. 2009.1. www.iucnredlist.org

Stiles, D., “The Marine Turtle Product Trade in Viet Nam”. Marine Turtle Newsletter 124:6-9, [2009?]
(Also one can check Seaturtle.org for Marine Turtle Newsletters overall and other related information.)

From http://www.swan.ac.uk/bs/turtle/hays_publications2.htm :

(fx:)

"As the Seas Warm". Science 313/2006.(August) [Pdf]

Hays GC, Broderick AC, Glen F, Godley BJ (2003). Climate change and sea turtles: a 150-year reconstruction of incubation temperatures at a major marine turtle rookery. Global Change Biology 9, 642-646. [Pdf]

Aiken JJ, Godley BJ, Broderick AC, Austin T, Ebanks-Petrie G, Hays GC (2001). Two hundred years after a commercial marine turtle fishery: the current status of marine turtles nesting in the Cayman Islands. Oryx 35, 145-151. [Pdf]

...And as additional mention, there's probably a lot from marine turtles at the Mongabay (fx), from where we find fx this article from plastic garbage on seas and it's words of wisdom (by Dr James, some kind of authority on this field apparently): "...hopeful aspect is that humans can easily begin addressing the solution, without major lifestyle changes...it's as simple as reducing packaging and moving towards alternative, biodegradable materials and recycling."


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Species Endangered (MS-Blog Series from) – V / 09

Mammoth

“When aiming to depict a world, that once existed, 30 000 years in the prehistoric past, and from where not any concise written word can't reach our times, one has to rely on: 1. Known facts 2. Conclusions based on those facts 3. Imagination “

(Björn Kúrten, 1984, Mammutens Rådare)^{Transl; W-G.}

• Class: Mammal
• Order: Proboscidea
• Latin name: Mammuthus (Primigenius /Columbi)
• Range: From Mid-Europe to Northern parts of Asia (Siberia) ; North American continent
• Population Status: EX (Extinct), the time varying regionally, about 14000-8000 B.C. on continents [~1700 B.C., on Wrangel island])

(a 2008 situation)

It may feel a bit inconsistent and obscure, that we are including an extinct species in our series. However, there's innumerable animals which have disappeared from the evolutionary continutation in the prehistoric pasts, during millions of years. This renown species particularly we've selected to represent a larger phenomenon, extinctions timed for the end of last ice age (or in wider sense usually described as the Quaternary extinction event). (Our selection) also has reasons from the fact that mammoths are among the better/best known species from that time.

If we now allow ourselves this exception, and it's selected from mammals it has to be the mammoth. At least from the terrestrial animals, from among sea mammals there could possibly be alternative choices. (In fact we might also consider some examples from disappeared insect and reptile species, but on this logic the latter would then have to be a dinosaur and that doesn't really much fit for the ecological or evolutionary limits we're trying to keep...and as well I notice my knowledge from dinosaur consisting from the three earliest parts of Jurassic park...) It seems also we've quite slipped for to present solely mammals since there's now already 4 of the total 6 so far in our series. Nevertheless, not the least because human family tree derives from mammals by origin, I'd still like later to include an example from some sea mammal (likely the whales), one from the carnivorous species and perhaps still yet another one from primates, our closest relatives according the evolutionary theory.



What makes most arguments on behalf selecting mammoth as species in this series is their long common path with humans in prehistory, reaching culturally even the present. In during couple decades mammoths have become a popular subject of many famous novels, most forcefully since the 1980s. The mentioned dinosaur films pushed them little away from spotlight in 1990s, but more recently there's afresh found popularity in films and books, fx such as Stephen Baxter's Silverhair (1999) and the followed novels in the serie (Icebones, Longtusk), which combined the recent knowledge and the mythical status of these animals.



But, not less important, the mammoths strong relationship to humans in (pre)history is found from the cave-paintings and sculpted art (see picture above), also there's many prehistoric tools and objects which are carved from mammoth ivory (as well the vast bone founds, mostly from Siberia, that still make a feasible industry for the specialized handicraft), and – not to forget - of course the archaeological founds, plenty of them made even before the 19^th century. If there had to be one animal species in connected to the humans in the ice-ages, most people would by first impression probably think about mammoths (although, fx deers, horses and as well as perhaps the cave-bears probably may have had equal place in the mythical and spiritual world of those distant ancestors).


Like goes the phrase, mammoths were the 'shaggy beasts' and the mammoth image mostly is settled for the best known/most common species, Mammuthus Primigenius(the wool mammoth). But in fact, they weren't beasts at all, not carnivores but large herbivores¹ that tramped on North-American and Eurasian continents during the recent glaciation periods. Contrary to sometimes misleading belief, mammoths did not inhabit the glaciers which at the time reached from North-pole to middle of those continents, but instead lived on plains that were limiting to the edges of glaciers (areas usually called as the mammoth steppe). In general that steppe is known to have been more rich from plants and animal species than similar areas today, although it was also very harsh from climatic conditions. Its vegetation probably was various enough to offer diet for several large grass-eating herbivores. At least on the southern parts also occasional trees would grow in the middle of grasslands. From preserved mammoths stomachs fx trenches of willows and birch have been found. Various animals lived on steppe, a lot more than are found on todays northern tundras, including deers, reindeers, wolves, and as well carnivorous lion-sized cats. Various smaller species too, fx marmots and lemmings were just a few examples. The mixture of elements from tundra and more temperates grasslands was characteristic for this steppe. Mammoths which were gigantic in proportions, about the same as elephants, are not believed to have had much predators. Possibly few carnivours that could occasionally threaten them were the sabretooth cats (Homotherium ; Smilodon). Injured or young smaller individuals may have gotten for their prey (ao animals), sometimes. Also, mammoth was among the most common species (from that the name, 'mammoth steppe'), only more abundant were horses and prehistoric bisons – the latter also larger in size than the surviving ones today. As is also quite renown, mammoth bones, tooths and skeletons, and even frozen individuals have been found from the Siberian permafrost in numbers (best preserved example being the Dima).


The wool mammoths evolutionary road goes back some 300 000 years when it evolved from the earlier mammoths (preceding species M. Meridionalis originated in warmer latitudes, and as it's successsor then about half million years ago evolved M. Trogontherii). From the latter further evolved the mentioned wool mammoths. On the North-American continent, since about 1.5 M years ago evolved slightly different comparable mammoth species, M.Colombi. It was (considerably) larger than M.Primigenius(wool mammoth was about 2.5 to 3.5 m tall and weighed about 4-6 tons). Also is supposed that M. Colombi might have lived on a bit warmer regions than wool mammoth, though not on the South-American region. With most probability species ranges not overlapped each other, although from some places remains from both have been found, and the wool mammoths skeletons (and frozen ones) have been found also from Alaska. In Any case these two presented the most abundant species before they both disappeared at the end of the latest ice-age, soon after the retreat of glaciers in the continents.


What has still remained somewhat unsolved (and as the most debated from mammoths for decades) is the question from their disappearance. Overally Pleistocene extinctions are known having followed supposed human arrival on various continents which makes a quite convincing argument on human participation on event (see the above Wikipedian link from that). In spite of that, on different continents this may have had more complex reasons too.


A well-known theory (among others) since the 1960s, is so called Overkill-theory, as such somewhat displaced nowadays. It focused largely on mammoths, since its main assumption was from the larger animals having been quickly annihilated by earliest arrivals on American continent, who (supposedly) were big game hunters (as the theory was concerned on N.A. and the first human settlement was earlier believed to date around 11200 B.C.). Originally, theory relied (largely) on founding of Clovis points(/Clovis spear points) first discovered at 1928, and since that from various places at mammoths skeletons and/or close their remains. More recent research has pushed the time of the first settlement further past(basically proves the theory inadequate). Also, Clovis people more likely were typical hunters and relied at least as much for various kinds of smaller prey, including fish, mussels, collecting grains and peanuts. They are known having inhabited large areas from the western part of continent, but little else from the culture is preserved until our times. The spear points have been found all around the Northern America, including Canada which also makes overkill-supposition more unlikely, as only about dozen mammoth kill sites at continent are known with certainty. (Fagan, 2005) So the theory becomes reasonable only if one thinks the arrivals having spread around continent surprisingly fast, and the spear points presenting a highly advanced paleolithic technology compared to preceding methods (of hunters). To certain level they perhaps might, but as the founds are such rare it only proves early humans having killed and eaten mammoths(as well as other herbivores), and as did also fx the Neanderthalians at least 100 000 years ago.


Since the mammoths disappeared only after the most recent glaciation, this also has given some argument on behalf the human causes. However, at the end of the Pleistocene climatic changes are known to have been more dramatic and varying by many ways, fx about 13000 years ago there might have been a sharp decline of several degrees in global temperatures in just couple decades (Lister-Bahn 1994) and 1000 years that followed were a period of cooler climates (in the middle of slow overall warming towards the end of glaciation)(Fagan 2005). That may have had many effects, but fx because the mammoths were large grass-eating animals it is reasonable to suppose that disappearance of ice-age tundra and spread of forests may have diminished their living area - It is also sometimes stated that mammoths might have become out-competed on those fewer remaining plains and grasslands by other herbivores, bisons mostly. The last mammoth populations might have evolved too specialized for the earlier conditions and therefore did not survive post glacial changes.

On the other hand it seems that these species were able to migrate in between regions, as one research notices that there may have been a 'return movement' of wool mammoth populations from the Beringia to Siberia. The likely cause for mammoths return via Beringia, could have been the climatic changes and in any case this seems to support a view from drastic changes in temperatures at the time(reason why the 'newcormers' replaced the earlier Siberian mammoths is not known, likely various possibilities exist). As other studies (DNA-researches) also seem to give an argument that also the populations of bisons in Beringia were affected by climate and declined in genetic diversity, it strenghtens the supposition that the dramatic changes (in climate) may have had serious effects on many species (and their ecological ranges). But even so, it is also often stated that no climate theory can adequately explain the total amount of the large species died out worldwide in about same period of time (the late Pleistocene).

From mammoths is also known that they may have survived somewhat longer on islands than on the continent. Best known example is from the Wrangel Island in Arctic sea, near East-Siberian coast, where the mammoths survived until about 3400 years before the present (most recent timing known they existed anywhere), but finally were – probably – wiped out by human, since human arrival on island has been timed close that (it's not known humans having hunted the mammoths there, though). As well, on St Paul Island near Alaskan coast, the mammoths survived until about 6000 B.C., extinction having followed from natural reasons, since humans are ruled out due that they first arrived on isolated island at 18^th century (Lister-Bahn [2007], p 163). Finally, from the examples of (dwarfed) isolated island mammoths, there is the Channel Islands 'pygmy mammoth' (subspecies M. Exilis), which had evolved to a lot smaller size in islands (during about 40000-20000 years period) after having swam to islands. Sea was then lower and the islands originally larger forming in the ice-age a 'super island', where mammoths would have grazed. It is believed that the disappearance closely correlates to (supposed) human arrival around 12900 years ago(Lister-Bahn [2007], p 160). Although, one feels likely the islands might well have been populated even earlier (how regularly is perhaps less clear). Whatever the most recent knowledge, I think any of preceding still gives only little explanation on behalf or against, since islands are isolated cases by any means. Yet, many believe the survival of several (prehistoric) animal species on islands long after the disappearance on mainland as strong argument (pro human caused event).


More recently (perhaps), as the most likely cause, has been raised the co-effect, where human hunters might have replenished last surviving populations. Seems logical to think so, largely because humans are known having extinct a number of animals, either remnants from earlier abundant populations declined from other reasons(like Steller's Sea Cow, Hydrodamalis gigas, Extinct at 1770s), and/or as well species which may have originally been numerous but vulnerable like Passenger pigeon, Ectopistes migratorius (last specimen died in captivity, 1914) - though concerning the latter mentioned, it has also been speculated the abundance of the bird having resulted from human caused changes in the ecological balance(Mann, 2005). In both cases, however, when species populations had weakened and become vulnerable the final period of annihilation(human caused) didn't take much longer than some 20-30 years. Even after loss of most of the suitable living habitat, mammoths disappearance would have taken a far longer period of time.


Last mammoths were disappearing from final parts of the Europe around 14000 years ago estimated, and the last founds, from Sweden and Denmark, are timed around 13000 years ago(Nogues-Bravo, 2008). Overally, mammoths vanished from across most of their known range in about 14000-10000 years ago. (But, in the southernmost places, South Europe and China they were gone already about 24000 years past). On the North-America the timing is closer to 11000 ago, supposedly M.Colombi having survived little later (about 500 years) than woolly mammoths.(Lister-Bahn [2007], 146).

Finally, a recent study seems to offer a combined explanation from the climatic and human caused influences, and it presents that major part of the most suitable climatic areas for (woolly) mammoths reduced continuously from 42000-6000 B.C., the species geographic range disappearing about 90 per cent during that time. Humans might have then finished the remaining pockets, where mammoths perhaps could have survived - like they did from earlier glaciation periods. According to that even limited hunting and low human population density might have been sufficient to cause final disappearance. The view is also supported with the last non islands mammoths founds located at northeastern Siberia, in the area classified by model as most suitable remaining living area 6000 B.C. The Wrangel island is believed to present an exception where vegetation and climate resembling ice-age tundra could have remained sometime longer (though according to model it wouldn't have been counted among those best suitable 'pockets' left in about that time, 4000 B.C. (Nogues-Bravo, 2008) Mammoths (species that come in the question here, M. Primigenius and mostly also M. Colombi), were from the evolutionary perspective species that roamed numerous and flourished during past the ice-ages, but it is supposable that whether there had been humans or not, might have after it either disappeared or been forced to adapt for somewhat more limited range/environments. And basically, it seems as most logical conclusion, so forth, case closed (at least for the wool mammoth); 'Increase of anthropogenic impacts in the Holocene are most likely to have been 'coup de grace' that set time and place for the extinction', like concluded in the research.

But since I feel some healthy suspicion - equally for statistics, quantitative analyses and lab-techs - I think it is worth the effort also consider all this from yet another perspective. At least because our series here mostly is focused on the endangered animals, not yet extinct.


As was noted, it is believed mammoths were not adapting for the spread of forests that increased in the end of last glacial, this being a (one) main cause for their disappearance. However, to the contrary it is sometimes assumed that their 'cousins', African savannah elephants (Loxodonta Africana) might have survived the recent (glaciation) periods because of the large forests that also existed in during ice-ages, though somewhat smaller in range. The glaciation(s) affected the African rain forests by reducing their geographic area, but they existed even during the so called glacial maximum (ie coldest period, when the sheets were at their largest). As consequence, todays savannah elephants therefore (supposedly) might have evolved from forest elephants for current species, only after ice-age(s) having populated the savannahs. The view is (was?) based on that from preceding times there is some 2 million year gap in the fossil remains of Loxodonta species (and rain forest conditions effectively prevent the formation of fossil remains). In during the same time Elephas-species were prevailing ones, their disappearance having happened in during those glaciation periods (Gamlin-Rohan, 1996). (The mentioned elephant species most probably include Elephas recki, abundant species in the past and E. antiquus which were found habitating even the European ranges still some 70 000 years ago - I guess there's plenty research about them too, though they seem less studied than mammoths) Be the elephants (recent) evolution and ecological ranges gone that way or not, the supposition doesn't completely hold because a study from current African elephant species DNA (forest and savannah), finds it more likely them being different species, that supposedly a result of the several millions years evolutionary divergence (Eggert-Rasner, 2002).


In any case, it is somewhat interesting because much from what is known about mammoths behavior is assumed by known/observed from the elephants. Also, it seems that both may have been common species in their particular habitat, but the post ice-age period (conditions) shows completely opposite. Not comparable with each other, since the geographic regions much differ and so did the climatic effects, but as mammoths disappeared, the current African elephants populations probably increased (and became as well very successful species in their habitat, like can be read from the following).


According to DNA-researches mammoths were found more related to Indian elephant, (Elephas maximus), but differences in between the three are relatively small. Mammoths fx were similarly slowly reproducing species (for an African elephant, as much cousin for mammoths as Indian, gestation period takes about 2 years, fx), a thing likely to increase species vulnerability. Nowadays less threatened from the two surviving elephant species, African elephant had populations counted in tens of millions still in the beginning of 19^th century. Today, the numbers are around half million specimen (in the early 1970s there were still about 2 million, but as result of increased killing for ivory, the species was conserved in 1990). If one then thinks that about 500-1000 years on most geographic ranges would have been 'needed' for the final days of the mammoths (that a direct following from human caused pressure or not) the similarities in between the two start to seem almost too alarming. In fact, the elephants are actually more in process of rapid endangerment than our prehistoric example ever was. The process only seems somewhat backwards, earlier major hunt largely having reduced their populations already. There's conservation areas today but they can't cover the whole of species ranges and as well the illegal pouching still is mentioned an existing threat.


So, perhaps our effort here was a little too devoted for these most interesting prehistoric questions and distant pasts. But all the same, it of course also quite well reflects that mythical image humans have always felt connected to mammoths. As the species is among the most researched ice-age topics, one feels it also makes quite convenient selection to this series. Even though there are various other (more peculiar) surviving species in existence today (not to forget the colourful frogs, birds, etc). And probably a reader, thousand years from now, would much agree with this last paragraph (not that I would suppose anyone reading this that far, or that being likely even...)

Pic (from Lister-Bahn, 1994) ; Mammoth-engraving in the Rouffignac-cave.

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Notes:

1. (Actually, seems that, we must have stolen that last sentence from somewhere, though I don't quite recollect from where...) But, on the other hand it can be remembered: mammoths were close relatives to elephants, animals that are not just among the most intelligent, but also known as one of the most (potentially) dangerous of them. So, on that basis the image of 'beast' can be argumented although not proven as most correct definition. Also the species huge size and proportions give some grounds for the view from humans point-of-view (not any beast of burden, anyway...)
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Reference (literature):


Lister, A. and Bahn, P, 1994, [2007], Mammoths - the Giants of the Ice-Age.

- Much of this text actually is based on information from the book. It's the best general source, likely. The newer edition contains more up-to-date knowledge and can be viewed on Google's book search (though, I've mostly relied on the older edition, from the reason that it's equally informative). However, one interested from mammoths easily finds lots researches, (also) sometimes from different views / focused on other aspects than the ones presented in the preceding.


Eggert, L.S., Rasner, C.A., Woodruff, D.S., 2002, The evolution and phylogeography of the African elephant inferred from mitochondrial DNA sequence and nuclear microsatellite markers. doi: 10.1098/rspb.2002.2070 Proc. R. Soc. Lond. B 7 October 2002 vol. 269 no. 1504 1993-2006. (Pdf - here) ; From Royal Society Proceedings (Biology)


Fagan, Brian, 2005, The long summer ; how climate changed civilization. NY.

Gamlin, L. and Rohan, A., 1996, Mysteries of the Rain Forest.


Kurtén, Bjorn, 1984, Mammutens rådare. (Fictional)


Mann, Charles C., 2005, 1491. New revelations of the America's before Columbus. NY.


Nogués-Bravo D, Rodríguez J, Hortal J, Batra P, Araújo MB (2008) Climate Change, Humans, and the Extinction of the Woolly Mammoth. PLoS Biol 6(4): e79. doi:10.1371/journal.pbio.0060079



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