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09 Aug 07 - 02:18 PM (#2122628) Subject: BS: Farewell Yangste River Dolphin From: Arnie That's it then for the Yangste River Dolphin. It really is tragic that this unique mammal, the last of it's species, has been wiped out by man's activities. There are other river dolphins in S.America but they are a different species. I had hoped that there are some Yangste dolphins in aquariums somewhere that may eventually be re-introduced, but I haven't heard of any. The newsclip I read said that this is the first large mammal to have become extinct in the last 50yrs - does anyone know which mammal was the last one to have this dubious distinction? |
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09 Aug 07 - 02:23 PM (#2122631) Subject: RE: BS: Farewell Yangste River Dolphin From: Peace Arnie: That is a tough one. Many have become extinct, but the 'net shows them as to where. It seems that Australia has the distinction of being the continent with the 'record' for killing them off. But, we do a fine job of it all over the world. We hunt them to extinction or poison their living area and then wonder what happened. Yeah. It makes me ashamed to be human. |
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09 Aug 07 - 02:31 PM (#2122637) Subject: RE: BS: Farewell Yangste River Dolphin From: Alba I was just reading about this online in 'The Independent' this morning Arnie. I'll include a link to the article. It lists the last Mammal to have become extinct as the Tazmanian Tiger back in 1936...Link to the sad facts Best wishes to you as always, Jude |
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09 Aug 07 - 03:07 PM (#2122655) Subject: RE: BS: Farewell Yangste River Dolphin From: Arnie Thanks Alba - I recall a TV programme a few years ago about the deliberate extermination of the Tasmanian tigers. There are occasional reported sightings of them in N.Zealand but no firm evidence of their continued existence so probably just wishful thinking. I know that a lot of animals became extinct before man arrived on the scene, but I really think that we can ill afford to lose any more - I mean, it's not as if new species are evolving to take their places any more. |
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09 Aug 07 - 03:08 PM (#2122657) Subject: RE: BS: Farewell Yangste River Dolphin From: Peace New species likely are evolving because there have been some discoveries in the past year or so. |
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09 Aug 07 - 03:17 PM (#2122660) Subject: RE: BS: Farewell Yangste River Dolphin From: Arnie Ah yes, but I suspect that these discoveries are old species that have simply (fortunately) managed to evade us so far! In fact, they probably haven't evaded us completely, but are usually well-known to indigenous peoples who have hunted them - they are not counted as 'discovered' until some Western explorer sees them and publishes the fact. |
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09 Aug 07 - 03:38 PM (#2122671) Subject: RE: BS: Farewell Yangste River Dolphin From: pdq Generally speaking, speciation occurs more rapidly as you go down the evolutionary chain. Bacteria evolve new species rapidly, sometimes in a few years. Large mammals (as in whales and bears) and large predatory birds (as in hawks and condors) may not produce a recognisable new species for thousands of years. In the mean time, more go extinct than appear. Most species on Earth are invertebrate animals: the insects, spiders and mites. They are all evolving new species at a rate somewhere between that of one-celled creatures and that of the large relic species. Most speciation requires when populations be separated by distance enough to prevent the exchange of genetic material. Islands and mountain tops (and caves) that are uninhabited (by humans) have huge numbers of undescribed species of both plants and animals. They are also usually small area and the species are vulnerable, especially to habitat destruction and from the ravages of new (pest) species such as rats that man brings with him. |
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09 Aug 07 - 04:33 PM (#2122701) Subject: RE: BS: Farewell Yangste River Dolphin From: katlaughing This was an especially poignant story for me as I know someone whose great-grandfather was one of the very first Westerners to travel up the Yangste. She and I were talking about it and wondering what in the world he would think if he could see what it has become. What a sad and thoroughly disgusting commentary on the idiocy of humankind. katsaddened |
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10 Aug 07 - 09:11 AM (#2123001) Subject: RE: BS: Farewell Yangste River Dolphin From: GUEST,Shimrod This is, surely, great news! We've been trying so hard to wipe out all the 'vermin' that we are forced to 'share' this planet with - and now we've succeeded with these pesky dolphins! Only a few more million species to go and then we can have the whole place to ourselves. Perhaps we can look forward to the day when we've concreted it all over and we're all jammed in shoulder to shoulder, fighting for air ... it'll be really great ... won't it? |
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10 Aug 07 - 09:18 AM (#2123012) Subject: RE: BS: Farewell Yangste River Dolphin From: Rapparee When humans encroach upon the home grounds of animals that's what happens. It's not so much hunting anymore that leads to animal extinction but human encroachment into habitat. You can't build cities or even villages, you can't clear farmland, you can't mine or lumber, you can't fish, you can't do anything without affecting animal habitat. What parents are going to say, "I'm not going to clear that piece of land; better to leave it as it is than to build a house for my family"? And there are far too many people. But I suspect that in one way or another Nature will correct to situation. As I've said before, the planet will survive, but there is no requirement for humanity to do so. |
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10 Aug 07 - 09:32 AM (#2123022) Subject: RE: BS: Farewell Yangste River Dolphin From: GUEST,PMB The rate of evolution is driven mostly by how fast the turnover is. Bacteria can have a new generation every few minutes. Many insects and the like can have several generations a year, most mammals a year upwards. Fecundity comes into it too- many fish produce tens of thousands of offspring at once, people generally one at a time. Obviously, the more offspring produced at a go, and the more often, the bigger chance selection has to work on them, and the faster this can affect our view of them as "variants" or "species". As for whether evolution will "fill in" for lost species, that depends on whether the ecological niche has been vacated (by hunting to extinction say), or totally destroyed as in the killing of a coral reef. If some members of another species occupying a (slightly?) different niche can take advantage of the opportunity, their offspring may have taken the first steps towards the spawning of a new species. A lot depends on what has been killing the Yangtse dolphins. If it is loss of habitat or food source, we can't look forward to their replacement. In any case, they and their ancestor species have lived there for 20 million years apparently; we humans are likely to be extinct before their replacement evolves. By the way, I don't subscribe to the idea that bacteria are "lower down" the evolutionary tree than we are- we and they have had exactly the same time to evolve since the beginning of life on Earth. I'd contend that we are (from the evolutionary point of view only of course) merely failed bacteria, that had to find another way of surviving that involved us in endless complications, Heath Robinson kludges and Machiavellian cellular politics. |
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10 Aug 07 - 09:53 AM (#2123037) Subject: RE: BS: Farewell Yangste River Dolphin From: katlaughing Some bits from the article, my emphasis in bold: It is the first large animal to be wiped from the planet for 50 years, and only the fourth entire mammal family to disappear in 500 years. And it was driven to its death by mankind... By Jeremy Laurance Published: 08 August 2007 After more than 20 million years on the planet, the Yangtze river dolphin is today officially declared extinct, the first species of cetacean (whale, dolphin or porpoise) to be driven from this planet by human activity. To blame for its demise is the increasing number of container ships that use the Yangtze, as well as the fishermen whose nets became an inadvertent hazard. This is no ordinary extinction of the kind that occurs frequently in a world of millions of still-evolving species. The Yangtze freshwater dolphin was a remarkable creature that separated from all other species so many millions of years ago, and had become so distinct, that it qualified as a mammal family in its own right. It is the first large vertebrate to have become extinct for 50 years and only the fourth entire mammal family to disappear since the time of Columbus, when Europeans began their colonisation of the world. Sam Turvey, conservation biologist at the Zoological Society of London, who led the expedition to find the Yangtze dolphin and is chief author of the paper, said: "The loss of such a unique and charismatic species is a shocking tragedy. This extinction represents the disappearance of a complete branch of the evolutionary tree of life and emphasises we have yet to take full responsibility in our role as guardians of the planet." The cause of the freshwater dolphin's demise was instead all too plain to the investigators. It had become a victim of the world's most populous country's race to get richer. One tenth of the world's population live in the Yangtze river basin. During the expedition, scientists counted 19,830 ships on the 1,669km of the river they surveyed - one large freight vessel every 800m. The Yangtze dolphin navigated by sonar - its eyes are useless in the murky water - but in a motorway jammed with container ships, coal barges and speed boats, its sonar was deafened and it ran a high risk of being hit or torn by propellers. An even greater threat came from the nets and 1,000m lines of hooks used by fishermen. Although they did not intend to catch dolphins, the creatures became entangled in the nets or lacerated by the bare hooks - almost half of all dead baiji found in the past few decades have died in this way. In addition, pollution had fouled their natural habitat and completion of the Three Gorges Dam worsened the decline in smaller fish on which the baiji fed. |
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10 Aug 07 - 10:44 AM (#2123081) Subject: RE: BS: Farewell Yangste River Dolphin From: GUEST This has been coming for a long time - this is not news. Many people have known the dolphin was under dire threat for decades, and nobody did a single thing about it. Since the construction of the Three Gorges dam the ecosystem of the Yangtze has suffered. Add into that the unregulated pollution of the river and overfishing from an increasing population and this was on the cards. The most sickening thing about this whole affair is the weeping and gnashing of teeth going on whilst the core issues are (as usual) ignored. China is turning into a totalitarian capitalist monstrosity and the world plays along gladly. It pollutes without fear of or regard for the consquences on the local population or wildlife. It continues to industrialise without regulation, often forcibly removing the popluation of entire villages that have been their for hundreds or possibly thousands of years, so it can build new industrial sites. These people loose their land and therefoppre their livelihoods - but who gives a tinker's cuss if it means we get cheap trainers? It's polluting Tibet - which it occupies illegally (can't see the Americans or British giving a toss about that one though - they stopped giving a shite about the freedom of the Tibetans when they discovered it made no financial sense to upset China), and in Africa it regularly wins construction contracts because it undercuts Western companies by virtue of the fact it disregards both the environment and local workers rights (no change there then - it's just the Chinese instead of the West shafting the Africans this time). We're all guilty of letting this happen. The Chinese Dragon is going to bite a lot harder yet. Across the world also look out for the imminent demise of: Boto (Amazon River Dolphin) Amazon Giant Otter Tigers: All species under severe threat across their range Whales: Several species will be hunted if the Japanese and Norweigans get their way etc etc etc |
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10 Aug 07 - 12:29 PM (#2123153) Subject: RE: BS: Farewell Yangste River Dolphin From: GUEST,ibo knock knock whos there adolf adolf who adolphin sorry,wrong river |
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11 Aug 07 - 04:28 AM (#2123548) Subject: RE: BS: Farewell Yangste River Dolphin From: Teribus How about this: http://www.timesonline.co.uk/tol/comment/columnists/ben_macintyre/article2231321.ece |
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11 Aug 07 - 07:59 AM (#2123607) Subject: RE: BS: Farewell Yangste River Dolphin From: Barry Finn Then there's the enviormental disaster happening in Lake Victoria & along the Nile. Barry |
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11 Aug 07 - 08:11 AM (#2123611) Subject: RE: BS: Farewell Yangste River Dolphin From: Peter T. Terrible. But it isn't clear to me why someone didn't think to save a few of them and put them in aquaria somewhere. Apart from the stupidity of the chinese authorities. I would have thought that WWF or someone would have at least tried...... yours, Peter T. |
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11 Aug 07 - 09:14 AM (#2123631) Subject: RE: BS: Farewell Yangste River Dolphin From: saulgoldie It is estimated that half of the world's species will be extinct within the next century if humans don't do something drastic. I'll go with what Rapaire said, that the planet will survive, but there is no requirement that humans do. By the way, extinction aside, has anyone checked the supply of fresh water lately? |