ILLUSTRATION FOR TIME BY TIM O'BRIEN
What Makes Us Different?
Not very much, when you look at our DNA. But those few tiny changes made all the difference in the world
Posted on 10/01/2006 3:14:48 AM PDT by PatrickHenry
You don't have to be a biologist or an anthropologist to see how closely the great apes—gorillas, chimpanzees, bonobos and orangutans—resemble us. Even a child can see that their bodies are pretty much the same as ours, apart from some exaggerated proportions and extra body hair. Apes have dexterous hands much like ours but unlike those of any other creature. And, most striking of all, their faces are uncannily expressive, showing a range of emotions that are eerily familiar. That's why we delight in seeing chimps wearing tuxedos, playing the drums or riding bicycles. It's why a potbellied gorilla scratching itself in the zoo reminds us of Uncle Ralph or Cousin Vinnie—and why, in a more unsettled reaction, Queen Victoria, on seeing an orangutan named Jenny at the London Zoo in 1842, declared the beast "frightful and painfully and disagreeably human."
It isn't just a superficial resemblance. Chimps, especially, not only look like us, they also share with us some human-like behaviors. They make and use tools and teach those skills to their offspring. They prey on other animals and occasionally murder each other. They have complex social hierarchies and some aspects of what anthropologists consider culture. They can't form words, but they can learn to communicate via sign language and symbols and to perform complex cognitive tasks. Scientists figured out decades ago that chimps are our nearest evolutionary cousins, roughly 98% to 99% identical to humans at the genetic level. When it comes to DNA, a human is closer to a chimp than a mouse is to a rat.
Yet tiny differences, sprinkled throughout the genome, have made all the difference. Agriculture, language, art, music, technology and philosophy—all the achievements that make us profoundly different from chimpanzees and make a chimp in a business suit seem so deeply ridiculous—are somehow encoded within minute fractions of our genetic code. Nobody yet knows precisely where they are or how they work, but somewhere in the nuclei of our cells are handfuls of amino acids, arranged in a specific order, that endow us with the brainpower to outthink and outdo our closest relatives on the tree of life. They give us the ability to speak and write and read, to compose symphonies, paint masterpieces and delve into the molecular biology that makes us what we are.
Until recently, there was no way to unravel these crucial differences. Exactly what gives us advantages like complex brains and the ability to walk upright—and certain disadvantages, including susceptibility to a particular type of malaria, aids and Alzheimer's, that don't seem to afflict chimps—remained a mystery.
But that's rapidly changing. Just a year ago, geneticists announced that they had sequenced a rough draft of the chimpanzee genome, allowing the first side-by-side comparisons of human and chimpanzee DNA. Already, that research has led to important discoveries about the development of the human brain over the past few million years and possibly about our ancestors' mating behavior as well.
And sometime in the next few weeks, a team led by molecular geneticist Svante Paabo of the Max Planck Institute for Evolutionary Anthropology, in Leipzig, Germany, will announce an even more stunning achievement: the sequencing of a significant fraction of the genome of Neanderthals—the human-like species we picture when we hear the word caveman—who are far closer to us genetically than chimps are. And though Neanderthals became extinct tens of thousands of years ago, Paabo is convinced he's on the way to reconstructing the entire genome of that long-lost relative, using DNA extracted, against all odds, from a 38,000-year-old bone.
Laid side by side, these three sets of genetic blueprints—plus the genomes of gorillas and other primates, which are already well on the way to being completely sequenced—will not only begin to explain precisely what makes us human but could lead to a better understanding of human diseases and how to treat them.
*** [Snip] ***
[Long article. For the rest, see the original: What Makes Us Different?]
|
" You don't have to be a biologist or an anthropologist to see how closely the great apes—gorillas, chimpanzees, bonobos and orangutans—resemble us "
Didn't read the whole article yet, but from the first sentence, let me guess --
It's about Howard Dean and JFKerry???
As much as I love Queen Vicki, she had it backward -- what's frightful and painful and disagreeable isn't how human they are; it's how simian we are.
First hijack attempt by #8?
Doesn't explain where everything else in the universe came from, but hey, you got start with something simple. Like how something with arms, legs, feet, brains, etc. can all pop out of a seed. Seems simple enough. Well, maybe not.
So why are there still Queens ?
Since we share about 98% of our DNA with chimps I guess we must be closely related.
And since we share about 30% of our DNA with a tapeworm then we must be closely related to the tapeworm, too.
We share about 30% of our DNA with mice so we must be even more closely related to mice than chimps or tapeworms or bananas or lots of other stuff.
Yep, that's really convincing evidence. </sarcasm>
If you're interested in learning about evolution, visit The List-O-Links.
If you'd like to understand the concept of speciation, visit Micro-evolution, Macro-evolution, and Speciation.
If you're serious about debating this issue, see How to argue against a scientific theory.
Well, it's still up to determine what parts of the DNA determine what. The setup of the cellular system would perhaps make for 20% shared DNA, who knows?
Your train of thought has derailed.
"Your train of thought has derailed."
Actually, mine is consistent, which is apparently more than can be said for yours.
It should have said 99% shared with mice.
Need more coffee.
infinite universes. and infinite time.
and if you need more than that to have the theories and formulas square up, just postulate more and more universes and more and more time.
And the more you postulate, the more foolish you become, and the further into the cave of denial you walk.
Try reading Genesis in the Holy Bible
So you don't know the difference between DNA and genomes.
Need more coffee.
Education too.
Fortunately, there are places things like this can be discussed without wading through this kind of crap.
Dipstick. If you knew anything about genetics you'd know that everything on the planet shares about 25 percent of its DNA. This is just more confirmation of common descent -- one of the bogeymen of the luddites.
Since we share about 98% of our DNA with chimps I guess we must be closely related.
And since we share about 30% of our DNA with a tapeworm then we must be closely related to the tapeworm, too.
We share about 30% of our DNA with mice so we must be even more closely related to mice than chimps or tapeworms or bananas or lots of other stuff. (emphasis mine)
Your math skills are as demonstrably deficient as your scientific knowledge.
98 is not equivalent to 30, and 30 is not greater than 98.
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.