Reverend AtheiStar Posted May 4, 2006 Share Posted May 4, 2006 http://www.nzherald.co.nz/section/story.cf...jectID=10380051 Presence of humans reverses evolution of finch 03.05.06 1.00pm By Steve Connor Humans are causing evolution to slip into reverse for one of the species of finches that is said to have inspired Charles Darwin after he returned from his famous visit to the Galapagos Islands. Scientists have found that one of "Darwin's finches" living in the remote Pacific archipelago has begun to lose the distinguishing trait that could be causing it to split into two different species. The medium ground finch is normally found in two distinct forms - individuals with a larger beak or those with a smaller beak - but when humans come to live alongside the finch, this "bimodal" beak size tends to disappear. The scientists believe that the arrival of people on the islands may be causing evolution to run in reverse by causing the two extreme versions of the ground finch to revert to individuals with intermediate beak sizes. In effect, people appear to be unwittingly eliminating the evolutionary disadvantage of having a beak that is half way in size between the two extremes, according to a study published in the "Proceedings of the Royal Society B". As yet the researchers do not understand why people are having this effect but the implications are that the influx of tourists and migrants to the Galapagos is helping to eradicate a source of biological diversity that has made the islands famous. "We need to make more effort to enable those species that are in the process of diversifying to continue to diversify and thereby generate new species," said Professor Andrew Hendry of McGill University in Montreal, who led the study. "It is appropriate to describe it as evolution in reverse. It's an evolutionary split within a species that is being reversed and we think human activity of some sort is responsible," he said. There are 14 different species of finch in the Galapagos and all are believed to have evolved from a single species that was blown by accident to the archipelago from the South American mainland. Darwin collected many dead specimens of the finches on his visit to the islands in 1835 but it was not until 1845 that he began to realise that they could have all evolved from a common stock. Darwin eventually recognised that it was the size and shape of each finch's beak that determined what it could eat and in which ecological niche is was best suited to survive. "Seeing this gradation and diversity of structure in one small, intimately related group of birds, one might really fancy that from an original paucity of birds in this archipelago, one species had been taken and modified for different ends," Darwin wrote in the 1845 edition of the Journal of Researches. The medium ground finch, as its name implies, feeds on medium-sized seeds. Its two most closely related species are the small ground finch, which feeds on small, soft seeds, and the large ground finch, which lives on larger, harder seeds. Professor Hendry explained that the medium finch differs from the other two species in that it has a "bimodal" population - in other words members of this species can be classified as having either large or small beaks, with few in between. Intermediate beak sizes for medium ground finches are rarely if ever seen in the wild, which indicates that normally it is a disadvantage to be born with a beak that is half way between the two size extremes. However, when the scientists studied populations of medium ground finches living near to human settlements on the island of Santa Cruz they found that most of them had reverted to having beaks of intermediate size. The human population of the town of Puerto Ayora on Santa Cruz - where the scientists studied medium ground finches - has mushroomed tenfold over the past 30 years. However, when the researchers analysed medium ground finches living away from densely-populated areas of the island they continued to find that the birds fell into one of two groups - those with big or those with small beaks. "What we found is that the process that is causing a species to split into two species is now being reversed," Professor Hendry said. The researchers can only speculate about the causes of the reverse. It could be the result of people introducing alien plants with intermediate-size seeds, or it could be the deliberate feeding of wild birds with imported rice. "Humans are changing the nature of the adaptive landscape. They are homogenising it. Being intermediate was once bad for the survival of this finch, now it is no longer the case for birds living near people," Professor Hendry said. "There's plenty of evidence of humans having caused species to go extinct but we're not in essence doing anything to reverse the loss of biodiversity. "Although the most immediate goal of biological conservation should be to preserve species at self-sustaining population sizes, a long-term goal should be to preserve their ability to diversify. "Only then can we reverse declines in biological diversity." Link to comment Share on other sites More sharing options...
pandora Posted May 4, 2006 Share Posted May 4, 2006 It seems obvious to me why this has occurred... tourists and inhabitants feed birds medium sized seeds in abundance, so the need for specialized beaks is not as great as it once was. Edit: Just read the rest of the article. It seems I am not so far off the mark. I'll have to think on it regarding if it is terribly detrimental to the environment or goals of conservation, though... Link to comment Share on other sites More sharing options...
Fweethawt Posted May 4, 2006 Share Posted May 4, 2006 Heh! The presence of certain humans reverses the evolution of a lot of things. Link to comment Share on other sites More sharing options...
Gnosis of Disbelief Posted May 4, 2006 Share Posted May 4, 2006 Not surprising. Humans are a big part of the environment, so naturally, we are affecting the evolution of other species. We've been doing this for a long time....after all, we're largely responsible for the evolution of the modern dog from the gray wolf. Link to comment Share on other sites More sharing options...
HuaiDan Posted May 4, 2006 Share Posted May 4, 2006 The scientists believe that the arrival of people on the islands may be causing evolution to run in reverse by causing the two extreme versions of the ground finch to revert to individuals with intermediate beak sizes. Evolution does not run in reverse!!!!!!!!! It's not like the DNA remembers what it used to be before it changed. I hate misleading language like this in pop science. Gives the creationists more ammo. Link to comment Share on other sites More sharing options...
TCH Posted May 4, 2006 Share Posted May 4, 2006 If the normal situation in the wild is that there is less food for these "medium" beak finches and one or more found an alternate food source they may tend to congregate in that location. I.e. Build nests, raise young, etc. Maybe the birds with other size beaks are not as smart. They have not figured out that these funny looking apes running around the island are an easy mark for a meal. Link to comment Share on other sites More sharing options...
Reverend AtheiStar Posted May 5, 2006 Author Share Posted May 5, 2006 The scientists believe that the arrival of people on the islands may be causing evolution to run in reverse by causing the two extreme versions of the ground finch to revert to individuals with intermediate beak sizes. Evolution does not run in reverse!!!!!!!!! It's not like the DNA remembers what it used to be before it changed. I hate misleading language like this in pop science. Gives the creationists more ammo. It certainly does. Evolution is a cumulative process that occurs across species. The DNA does not have to remember. Natural selection can easily push a beak size back and forth and back again as this is really a very, very smal change. It's not like we're talking about humans devolving into apes -- though there was that controversial case about the Turkish family with the strange apish behavior that was "mapped the defect to a region of the genome called chromosome 17p, a site of some of the biggest genetic differences between humans and chimps." Link to comment Share on other sites More sharing options...
pandora Posted May 5, 2006 Share Posted May 5, 2006 Wow! You are the first person I have run across that knows that little tidbit. I've mentioned it in real life a few times, and no one else believed me. I though I was dumb! LOL The chickens with teeth thing was pretty cool too. Truth is stranger than fiction. Link to comment Share on other sites More sharing options...
redneck22 Posted May 5, 2006 Share Posted May 5, 2006 The scientists believe that the arrival of people on the islands may be causing evolution to run in reverse by causing the two extreme versions of the ground finch to revert to individuals with intermediate beak sizes. Evolution does not run in reverse!!!!!!!!! It's not like the DNA remembers what it used to be before it changed. I hate misleading language like this in pop science. Gives the creationists more ammo. It certainly does. Evolution is a cumulative process that occurs across species. The DNA does not have to remember. Natural selection can easily push a beak size back and forth and back again as this is really a very, very smal change. It's not like we're talking about humans devolving into apes -- though there was that controversial case about the Turkish family with the strange apish behavior that was "mapped the defect to a region of the genome called chromosome 17p, a site of some of the biggest genetic differences between humans and chimps." I read the article on the unfortunate Turkish family and it mentions the possibility of the loss of genes that were previously gained. Are you aware of any website that could explain to me how genes are gained in the evolutionary process. Link to comment Share on other sites More sharing options...
Reverend AtheiStar Posted May 5, 2006 Author Share Posted May 5, 2006 The scientists believe that the arrival of people on the islands may be causing evolution to run in reverse by causing the two extreme versions of the ground finch to revert to individuals with intermediate beak sizes. Evolution does not run in reverse!!!!!!!!! It's not like the DNA remembers what it used to be before it changed. I hate misleading language like this in pop science. Gives the creationists more ammo. It certainly does. Evolution is a cumulative process that occurs across species. The DNA does not have to remember. Natural selection can easily push a beak size back and forth and back again as this is really a very, very smal change. It's not like we're talking about humans devolving into apes -- though there was that controversial case about the Turkish family with the strange apish behavior that was "mapped the defect to a region of the genome called chromosome 17p, a site of some of the biggest genetic differences between humans and chimps." I read the article on the unfortunate Turkish family and it mentions the possibility of the loss of genes that were previously gained. Are you aware of any website that could explain to me how genes are gained in the evolutionary process. Sure, mine. Since you're most likely a creationist, here's a wonderful primer on how evolution works and the massive evdience behind it. Before you dismiss it, though, keep in mind it was written by a theist like you. He's a theistic evolutionist. Check it out: http://www.reverendatheistar.com/macroevolution.htm Link to comment Share on other sites More sharing options...
Skankboy Posted May 5, 2006 Share Posted May 5, 2006 I read the article on the unfortunate Turkish family and it mentions the possibility of the loss of genes that were previously gained. Are you aware of any website that could explain to me how genes are gained in the evolutionary process. Redneck, are you serious? Didn't YOU provided the article in the "Those Damn Dogs" thread that explained this? “DOG BREED SECRETS REVEALED, as described in ScienceNOW, 14 Dec 2004. The distinctive features of some dog breeds have been found to be due to alterations in 'tandem repeats' – regions of DNA where the same sequence is repeated many times. When these regions are being copied the machinery that does the copying can sometime lose track of where it is up to and leave out some of the repeated sequences or add in a few extra copies. Link to comment Share on other sites More sharing options...
A T Thunderbird Posted May 5, 2006 Share Posted May 5, 2006 This is proof of devolution which invalidates Darwin. It's not roof for ID but for the creationist idea of devolution which is one step forward for Christianity. Praise the Lord for the beautiful creation which He created! Link to comment Share on other sites More sharing options...
Reverend AtheiStar Posted May 6, 2006 Author Share Posted May 6, 2006 This is proof of devolution which invalidates Darwin. It's not roof for ID but for the creationist idea of devolution which is one step forward for Christianity. Praise the Lord for the beautiful creation which He created! How does devolution invalidate the whole of evolution? That makes no sense. Evolution goes back and forth. Species adapt to changing conditions. Sometimes those conditions swing back to what they once were. Hence devolution. Why does religion so often stop a thinking mind? Can you really not see this? It's so simple! Creationists are so strange. They're so stuck in the mindset of worshipping their Christ that when it comes to attacking evolution, they go specifically after Darwin. Darwin no longer exists. His ideas were great, but evolution has moved on. Why not attack modern evolutionists? Oh yeah, they're alive and can fight back! lol... Evolution is neutral with respect to Christianity. Sure, it invalidates literal Christianity, but anyone who believes in a literal interpretation has no business being involved with any kind of science as these primitive, nonsensical beliefs are anti-science. The two can't mix. They're like oil and water. Scratch that. They're like sludge and water. Evolution is free moving and always changing to adapt with the new evidence that is found. Literalism is just sits there stays the disgusting sludge it always was. It's a pollutant and it tends to corrupt anything it touches. Imaginary friends can't create. They're completely impotent. You can imagine that your god can actually do things, but in reality he is just a program running in your mind. Care to disprove me? Make your pet god do something. Just one trick. Come on! Can he appear in front of me and do something that even a dog could do, like roll over? How 'bout fetch? Go get it, god! Good boy! Here's a bone. Go chew it outside, though. I don't want you making a mess in here like last time! lol... Link to comment Share on other sites More sharing options...
theunraveler Posted May 6, 2006 Share Posted May 6, 2006 deevolution in action Link to comment Share on other sites More sharing options...
Ouroboros Posted May 6, 2006 Share Posted May 6, 2006 I read the article on the unfortunate Turkish family and it mentions the possibility of the loss of genes that were previously gained. Are you aware of any website that could explain to me how genes are gained in the evolutionary process. You provided the reference in the Damn Dogs thread: “DOG BREED SECRETS REVEALED, as described in ScienceNOW, 14 Dec 2004. The distinctive features of some dog breeds have been found to be due to alterations in 'tandem repeats' – regions of DNA where the same sequence is repeated many times. When these regions are being copied the machinery that does the copying can sometime lose track of where it is up to and leave out some of the repeated sequences or add in a few extra copies. Read the underlined, red, bolded, extra large text. Which part of "add in a few extra copies" don't you understand? Link to comment Share on other sites More sharing options...
narcissist Posted May 7, 2006 Share Posted May 7, 2006 This is proof of devolution which invalidates Darwin. HAHA. The DaVinci Code invalidates the Bible. Praise God for Dan Brown! Link to comment Share on other sites More sharing options...
Skankboy Posted May 8, 2006 Share Posted May 8, 2006 Read the underlined, red, bolded, extra large text. Which part of "add in a few extra copies" don't you understand? It's a bit like this eh Han? Link to comment Share on other sites More sharing options...
Ouroboros Posted May 8, 2006 Share Posted May 8, 2006 Read the underlined, red, bolded, extra large text. Which part of "add in a few extra copies" don't you understand? It's a bit like this eh Han? Yup. Except my head is more swollen and covered in blood... Link to comment Share on other sites More sharing options...
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