Posted on 07/20/2006 6:58:11 AM PDT by PatrickHenry
The ability to spot venomous snakes may have played a major role in the evolution of monkeys, apes and humans, according to a new hypothesis by Lynne Isbell, professor of anthropology at UC Davis. The work is published in the July issue of the Journal of Human Evolution.
Primates have good vision, enlarged brains, and grasping hands and feet, and use their vision to guide reaching and grasping. Scientists have thought that these characteristics evolved together as early primates used their hands and eyes to grab insects and other small prey, or to handle and examine fruit and other foods.
Isbell suggests instead that primates developed good close-up eyesight to avoid a dangerous predator -- the snake.
"A snake is the only predator you really need to see close up. If it's a long way away it's not dangerous," Isbell said.
Neurological studies by others show that the structure of the brain's visual system does not actually fit with the idea that vision evolved along with reaching and grasping, Isbell said. But the visual system does seem to be well connected to the "fear module," brain structures involved in vigilance, fear and learning.
Fossils and DNA evidence show that snakes were likely the first serious predators of modern mammals, which evolved about 100 million years ago. Fossils of snakes with mouths big enough to eat those mammals appear at about the same time. Other animals that could have eaten our ancestors, such as big cats, and hawks and eagles, evolved much later.
Venomous snakes evolved about 60 million years ago, raising the stakes and forcing primates to get better at detecting them.
"There's an evolutionary arms race between the predators and prey. Primates get better at spotting and avoiding snakes, so the snakes get better at concealment, or more venomous, and the primates respond," Isbell said.
Some primate groups less threatened by snakes show fewer signs of evolutionary pressure to evolve better vision. For example, the lemurs of Madagascar do not have any venomous snakes in their environment, and in evolutionary terms "have stayed where they are," Isbell said. In South America, monkeys arrived millions of years before venomous snakes, and show less specialization in their visual system compared with Old World monkeys and apes, which all have good vision, including color.
Having evolved for one purpose, a good eye for color, detail and movement later became useful for other purposes, such as social interactions in groups.
Isbell is currently working on a book about primate origins, including her snake hypothesis.
From a judicial point of view I can point you to the Historical evidence of the resurrection of Jesus Christ as a proof text of supernatural reality. He rose from the dead and was witnessed by multitudes to authenticate His message that He is the Creator of the universe and is supernatural.
Because you choose to disregard the evidence is a philosophical decision on your part.
Human beings were created with the capacity to formulate ideas and be creative. We were created in the image of our Creator. His creative powers inspire us to expand our lives by discovering His handy-work.
Let's just say everything revolves around the Earth - then we don't have to worry about pesky things like scientific research.
Funny you should mention that. Why just the other day, on this very forum, a creationist asserted that the earth is the center of the entire universe.
Seriously? On which thread? I remember that a creationist once claimed that evolutionists think the earth is the center of the universe, but this is a new one.
That's the one! THANK YOU!
Here's my placemarker.
http://www.freerepublic.com/focus/news/1653902/posts?page=1030#1030
The marine ancestors of arachnids (spiders, scorpions and mites) are even more alien looking...
The biggest fossils known are more than six feet in length. This makes the Eurypterids or "sea scorpions" the largest arthropods that ever existed, so far as is known.
I think the closest living marine relative of the spiders would be another odd looking creature; the horseshoe crab.
Hey, I'm an entrepreneur, a big picture guy. My interests are cosmic. I come up with ideas and then hire geeks to do the grunt work. You have your assignment. Now start coding!
Hey, I'm an entrepreneur, a big picture guy. My interests are cosmic. I come up with ideas and then hire geeks to do the grunt work. You have your assignment. Now start coding!
You've perfectly captured the spirit of the 'entrepreneurial' top management of three companies I worked for in a previous life. Unfortunately, they all quickly went belly up bankrupt (and this was before the Internet boom and bust). But they sure knew how to motivate. :)
I was hoping to imitate the ways of the intelligent designer.
You can start by eradicating all evidence of your existence.
Many have tried ...
Besides, Jesus' rising or not has no bearing on a supernatural cause for the diversity of life on Earth. I understand your trying to shift the goalposts as it were. If I didn't have any physical, tangible evidence to support my position I'd probably go for the smoke-and-mirrors route myself.
Since they couldn't possibly have observed this process, how did they come up with it?
Eww, you sound like a project manager.
I somehow missed that post, with the creationist asserting that the earth is the center of the entire universe...thanks for posting the links that lead back to that...
I am never surprised when a creationist comes up with such whacky views, I am assuming, based on their own particular interpretation of the Bible...
After all, there are those, who advocate that using modern medicine goes against their personal interpretation of the Bible...some think that using electricity and modern conveniences goes against their personal interpretation of the Bible...this is never surprising, its actually to be expected...everyone with their own interpretation of what the Bible is saying, come to very different and usually conflicting ideas...
People will always disagree...some say the Bible demands execution for murderers...others disagree and say the Bible prohibits execution of anyone for any reason...some claim Mary remained ever virgin, according to the Bible, others disagree and say that Mary had sex and had other children, according to the Bible....some claim the Bible shows that the church was built on Peter, others claim that this is a lie, and that the church was built on Christ...and on and on and on....
And everyone is just soooo certain, that their view alone and that their personal interpretation of the Bible, alone, is the one and only correct and clear understanding of what the Bible says...and that everyone else is soooo wrong and damned to Hell...
Right...the way all these folks go on and on about how right they are about their 'God', and their personal interpretation of the Bible, one would think that they believe that they themselves are the genuine spokesperson for God, on earth...
Too many think that they are experts on God...that they can with authority speak for God...I would submit, that none here speak for God...they speak only for their own personal interpretation of the Bible, and that is all they can speak for...
Why are you going off topic?
I assume you have an opinion about whether OJ killed Nichole. How did you come up with it?
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