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Ape-Human Split Moved Back By Millions Of Years
E++99 writes in to let us know about a development in paleo-anthropology. It seems that up until now, scientific consensus has placed the divergence of man from the ape line five to six million years ago (based on "genetic distances"). But newly discovered fossils in Ethiopia place the divergence at least twice as far back, and perhaps as long ago as 20 million years. They also largely put to rest any doubts that man and modern apes both emerged from Africa. From the article: "The trail in the hunt for physical evidence of our human ancestors goes cold some six or seven million years ago... Beyond that... fossils of early humans from the Miocene period, 23 to five million years ago, disappear. Fossils of early apes especially during the critical period of 14 to eight million years ago were virtually non-existent — until now... [T]he new fossils, dubbed 'Chororapithecus abyssinicus' by the team of Japanese and Ethiopian paleo-anthropologists who found them, place the early ancestors of the modern day gorilla 10 to 10.5 million years in the past, suggesting that the human-ape split occurred before that."
They found fossil teeth. They identified them as coming from after the gorilla-human split. They dated them to 10.5 mya to 10.0 mya. Their colleges agreed. Using such conditionals is how responsible scientists and scientific journalists speak.
You MAY have been conditioned in favor of absolute and sweeping "scientific" statements from watching Al Gore movies.
Independent informed opinions from the article:
"This is a major breakthrough in our understanding of the origin of humanity," Yohannes Haile-Selassie, a physical anthropologist at the Cleveland Museum of Natural History
Paleoanthropologist Owen Lovejoy of Kent State University in Ohio... described the fossils as "a critically important discovery," a view echoed by several other scientists who had read the paper or seen the artifacts.
Apes are monophyletic, because apes include humans. You are correct though, that the non-human apes are paraphyletic, because the closest living relative of the chimps are humans.
My impression of the Nature article (subscription required) is that the authors are claiming that their paleontologic find pushes the gorilla split (from the human-chimp lineage) back to ~12 million years. Based on this, they essentially recalibrate the molecular clock as it relates to several of the ape divergences. This information is in section 5 of the paper's online supplementary materials (subscription not required), not the body of the article. Keep in mind that supplementary materials generally aren't peer-reviewed as rigorously as the rest of the article.
However, Hominoidea, the "ape clade", certainly includes humans.
Actually, mammals appeared more or less at the same time dinosaurs did. It's just their success came after dinosaurs vanished. There were many species of mammals contemporary to dinosaurs.
Dinosaurs died out 65 million years ago at the KT boundary.
Prior to that time the mammal line had already split much more than we previously gave it credit for, a lot of the main groups were developed. This article is a fairly worthless crock. Basically some teeth were found that looked vaguely gorilla like and dated back 10 million years. So we know that there was some ape-like creature with a gorilla-like diet 10 million years ago. However, saying that this is the Ape-Human split is as stupid as saying it's the Human-Mammal split. Humans are apes. We are clearly within the same grouping of gorillas, orangutans, and chimps. There's no real grouping of animals which includes those yet excludes humans. This find perhaps sets back the date of chimp-gorilla split but not "human-ape". That's just stupid. Chimp-human is a split which dates back about 4-6 million years. Gorilla-chimp goes back 8 million years, though perhaps 10 if this isn't just some offshoot.
Finally, 10 million years is about 2/17th of 85 million years. Basically your math is off, and you're using old information, and to top it off this article is totally stupid. It's 10 million year old gorilla-like teeth. It actually has almost nothing to do with human evolution, though if you studied gorilla evolution you might care. Though, it's even weak evidence that it's actually a gorilla just that it had a diet like that of a gorilla.
It is no longer uncommon to be uncommon.
Any theory is subject to revision based on new evidence. Nobody's trying to "PROVE evolution". Common descent is the best explanation for the dual-nested hierarchy that we see; a theory is simply the best explanation.
Laws do not persuade just because they threaten. --Seneca
As someone else pointed out, the KT boundary was 65 Mya, not 85. Also, early mammals of that era are usually described as "shrew-like" (also nocturnal, which is why we all have different color vision systems than reptiles), so probably even smaller than that.
The line that would eventually give rise to the mammals split from the reptile lineage before the emergency of the dinosaurs (the number cited is 324 Mya); look up "synapsid" for more information. It was actually the dominant type of land fauna until the greatest mass extinction in history at the end of the Permian (250 Mya), which was followed by the emergence of the dinosaurs. There were large synapsids in the early years of the Mesozoic, but the branch that would give rise to the mammals--the cynodonts--emerged about 220 Mya. There's a rather exhaustive description over at Wikipedia; also see talkorigins.
On a more relevant note, consider the whales. It appears now that whales are more closely related to hippos than hippos are to cows. (Again, see Wikipedia for a good summary.) This was mightily confusing, because we generally take phenotypic change as an indicator of distance between species. The important thing to remember here is that species change due to pressures put on them. Rapid pressures brought on by migration into a new environment (like the sea, for example) will cause a greater rate of phenotype change than would exist if the environment remained constant--consider the shark for this latter case.
Also, as another commenter has pointed out, the mammalian lineages had already split at that point; divergence points for some groups of mammals are after the KT boundary, but many are before it. However, it appears that even though the groups were separate, they all looked pretty much alike until they migrated into the niches vacated by the dinosaurs and diverged widely.
And lastly, your math isn't quite right. 7 million years (the divergence point for the chimp and human lineages, notwithstanding a very poorly written article) is more like a tenth of the time it took to get from (many kinds of!) shrew-like mammals to a similar level of mammalian diversity to what we see today.
Laws do not persuade just because they threaten. --Seneca
The phrase you are looking for is "teapot atheist".
Bertrand Russell posed the postulate that there is a teapot in orbit around the Sun between Earth and Mars. Because the teapot is too small, we cannot detect it with even our best telescopes (although this may change in the future). Since we cannot disprove the existence of the teapot, must we be "teapot agnostics"? Technically, yes, but from a practical standpoint, we are all "teapot atheists".
The problem is that there are an infinite number of bogus postulates. Unless we are to be agnostic about everything (Will the Sun really rise tomorrow?), we must go by the preponderance of evidence. The lack of evidence otherwise suggests that there is no God, which is my current belief. If the evidence changes, so will my beliefs.
Incidentally, the "bogus religion" theory throws a monkey wrench into Pascal's Wager. Pascal's Wager assumes that the only two possibilities are a Christian God who rewards belief and no God at all. What if, for example, God rewarded skepticism? What if Hinduism is correct? Since there is no solid evidence to suggest that this religion is any more correct than any other religion, we cannot make such an assumption.
No, this latest discovery doesn't break science. This kind of discovery is exactly what science is all about - constantly looking for new evidence to enhance our understanding, whether or not that evidence supports the current theory. Scientific skepticism isn't about being closed to new ideas, it's about treating every theory with a critical eye and constantly trying to prove yourself wrong.
When was the last time you heard a Fundamentalist Christian utter the words, "I was wrong"?
Nebraska man
A lie and a fake for 40 years.
Nebraska man was speculation, not a "fake" or a "lie", that was revealed to be porcine rather than hominid during peer review, and it was disproven in three years with the finder of the tooth declaring doubts within two. It was never accepted as a human ancestor, and it certainly didn't last for forty years.
You are a liar. Anyone who has done even a little bit of research would see that your claims regarding Nebraska Man are a shameless, brazen lie.
What do you believe that you are proving by lying so transparently? Why should anyone believe anything that you say when you lie so blatantly?
STOP MISUSING APOSTROPHES, YOU MORONS!!!
Just for reference, my Y-chromosome goes back to the Near East 10,000 years ago when a particular non-damaging mutation occurred. Fossils aren't the only things that contradict creationism. So does DNA research.
Keep in mind that DNA determines mainly cellular structure and everything since viruses has a cellular structure. So the basic mechanisms of cellular function are going to remain relatively constant across billions of years.
Humans are 98.4% genetically identical to chimpanzees, 80% to rats, 40% to chickens; based on the complete genomic sequencing of these 4 species and a lot of educated guesswork by the folks involved - and big error bars on those estimates. :) (pigs havent' been sequenced yet, so that would entail a lot more guesswork, but obviously they would be closer to rats than chickens since they are mammals so your 40-60 guess isn't that bad (for birds and mammals, at least.) My guess is that those percentages will change quite a bit - especially when we understand more about junk dna - but the relative relations to humans will remain in the same ballpark.
I think religionists tend to have a problem with mathematics, logic, critical reasoning skills, and various of the sciences in general. I believe the concept is called "low intelligence levels." (Purely supposition on my part, of course.)