Posted on 02/08/2005 3:50:43 AM PST by PatrickHenry
A group of four-footed mammals that flourished worldwide for 40 million years and then died out in the ice ages is the missing link between the whale and its not-so-obvious nearest relative, the hippopotamus.
The conclusion by University of California, Berkeley, post-doctoral fellow Jean-Renaud Boisserie and his French colleagues finally puts to rest the long-standing notion that the hippo is actually related to the pig or to its close relative, the South American peccary. In doing so, the finding reconciles the fossil record with the 20-year-old claim that molecular evidence points to the whale as the closest relative of the hippo.
"The problem with hippos is, if you look at the general shape of the animal it could be related to horses, as the ancient Greeks thought, or pigs, as modern scientists thought, while molecular phylogeny shows a close relationship with whales," said Boisserie. "But cetaceans – whales, porpoises and dolphins – don't look anything like hippos. There is a 40-million-year gap between fossils of early cetaceans and early hippos."
In a paper appearing this week in the Online Early Edition of the Proceedings of the National Academy of Sciences, Boisserie and colleagues Michel Brunet and Fabrice Lihoreau fill in this gap by proposing that whales and hippos had a common water-loving ancestor 50 to 60 million years ago that evolved and split into two groups: the early cetaceans, which eventually spurned land altogether and became totally aquatic; and a large and diverse group of four-legged beasts called anthracotheres. The pig-like anthracotheres, which blossomed over a 40-million-year period into at least 37 distinct genera on all continents except Oceania and South America, died out less than 2 and a half million years ago, leaving only one descendent: the hippopotamus.
This proposal places whales squarely within the large group of cloven-hoofed mammals (even-toed ungulates) known collectively as the Artiodactyla – the group that includes cows, pigs, sheep, antelopes, camels, giraffes and most of the large land animals. Rather than separating whales from the rest of the mammals, the new study supports a 1997 proposal to place the legless whales and dolphins together with the cloven-hoofed mammals in a group named Cetartiodactyla.
"Our study shows that these groups are not as unrelated as thought by morphologists," Boisserie said, referring to scientists who classify organisms based on their physical characteristics or morphology. "Cetaceans are artiodactyls, but very derived artiodactyls."
The origin of hippos has been debated vociferously for nearly 200 years, ever since the animals were rediscovered by pioneering French paleontologist Georges Cuvier and others. Their conclusion that hippos are closely related to pigs and peccaries was based primarily on their interpretation of the ridges on the molars of these species, Boisserie said.
"In this particular case, you can't really rely on the dentition, however," Boisserie said. "Teeth are the best preserved and most numerous fossils, and analysis of teeth is very important in paleontology, but they are subject to lots of environmental processes and can quickly adapt to the outside world. So, most characteristics are not dependable indications of relationships between major groups of mammals. Teeth are not as reliable as people thought."
As scientists found more fossils of early hippos and anthracotheres, a competing hypothesis roiled the waters: that hippos are descendents of the anthracotheres.
All this was thrown into disarray in 1985 when UC Berkeley's Vincent Sarich, a pioneer of the field of molecular evolution and now a professor emeritus of anthropology, analyzed blood proteins and saw a close relationship between hippos and whales. A subsequent analysis of mitochondrial, nuclear and ribosomal DNA only solidified this relationship.
Though most biologists now agree that whales and hippos are first cousins, they continue to clash over how whales and hippos are related, and where they belong within the even-toed ungulates, the artiodactyls. A major roadblock to linking whales with hippos was the lack of any fossils that appeared intermediate between the two. In fact, it was a bit embarrassing for paleontologists because the claimed link between the two would mean that one of the major radiations of mammals – the one that led to cetaceans, which represent the most successful re-adaptation to life in water – had an origin deeply nested within the artiodactyls, and that morphologists had failed to recognize it.
This new analysis finally brings the fossil evidence into accord with the molecular data, showing that whales and hippos indeed are one another's closest relatives.
"This work provides another important step for the reconciliation between molecular- and morphology-based phylogenies, and indicates new tracks for research on emergence of cetaceans," Boisserie said.
Boisserie became a hippo specialist while digging with Brunet for early human ancestors in the African republic of Chad. Most hominid fossils earlier than about 2 million years ago are found in association with hippo fossils, implying that they lived in the same biotopes and that hippos later became a source of food for our distant ancestors. Hippos first developed in Africa 16 million years ago and exploded in number around 8 million years ago, Boisserie said.
Now a post-doctoral fellow in the Human Evolution Research Center run by integrative biology professor Tim White at UC Berkeley, Boisserie decided to attempt a resolution of the conflict between the molecular data and the fossil record. New whale fossils discovered in Pakistan in 2001, some of which have limb characteristics similar to artiodactyls, drew a more certain link between whales and artiodactyls. Boisserie and his colleagues conducted a phylogenetic analysis of new and previous hippo, whale and anthracothere fossils and were able to argue persuasively that anthracotheres are the missing link between hippos and cetaceans.
While the common ancestor of cetaceans and anthracotheres probably wasn't fully aquatic, it likely lived around water, he said. And while many anthracotheres appear to have been adapted to life in water, all of the youngest fossils of anthracotheres, hippos and cetaceans are aquatic or semi-aquatic.
"Our study is the most complete to date, including lots of different taxa and a lot of new characteristics," Boisserie said. "Our results are very robust and a good alternative to our findings is still to be formulated."
Brunet is associated with the Laboratoire de Géobiologie, Biochronologie et Paléontologie Humaine at the Université de Poitiers and with the Collège de France in Paris. Lihoreau is a post-doctoral fellow in the Département de Paléontologie of the Université de N'Djaména in Chad.
The work was supported in part by the Mission Paléoanthropologique Franco-Tchadienne, which is co-directed by Brunet and Patrick Vignaud of the Université de Poitiers, and in part by funds to Boisserie from the Fondation Fyssen, the French Ministère des Affaires Etrangères and the National Science Foundation's Revealing Hominid Origins Initiative, which is co-directed by Tim White and Clark Howell of UC Berkeley.
It is easy to tell a good Christian in some aspects.
Hating anything is not good. Departing from the basics of theology in the Nicene Creed is not good.
Lying is not good.
Creationists practice all of the above and by doing so, distort the Gospel. This is either heresy or blasphemy of the Holy Spirit depending on the extent.
The leaders of creationism are scam artists who have usurped Christianity to make money, not unlike some of the televangelists (many of whom have promulgated the same apostate dogma).
"I have not quoted the Bible."
Sorry, I must have been thinking of someone else.
http://www.bloomberg.com/apps/news?pid=10000103&sid=azBO_AumTJhs
I couldn't post this as a separate story because Bloomberg is blocked. It is very disturbing.
It shows the rapid evolution of AIDs into a very resistant strain, resistant to all known treatments. It also does not have the long latent period of the first strains. It only stays as HIV 3 months before turning into full blown Aids.
This probably is the precursor to pnuemonic AIDs, which would make the plagues of the middle ages look mild in comparison. It would be more devasting than nuclear warfare.
I can't access Bloomberg either. It will show up elsewhere.
I'm not sure what you mean by creatiionism. For instance, ID is not Biblical literalism.
Does ID allow us to pose scientifically useful questions? As it is now, sure. It's a new concept, however, and no layers of dogma have become attached to it.
That, I think, is where a legitimate concern lies because dogma does prohibit scientific inquiry.
What ID now does, ironically, is challenge the existing dogma of seamless, undirected evolution. Science shouldn't put itself in the position of claiming that God doesn't exist (which many dogmatic evolutionists do) or that God can't or won't interact with the creative process (which is standard evolutionary theory)
If the reality is that God exists and interacts with creation -- as faith and reason tell me -- science should reflect this, and until relatively recently did. And the boundaries religion places on science -- Mengele comes most quickly to mind -- most here would support. For Pete's sake, Darwin wrote in the Victorian era.
Can ID be falsified? Well, it's math based so yes.
And IC can certainly be falsified. Just consider the debate on Behe's flagellum. It can't be reduced/ yes it can, look at how the proteins exactly match the secreation apparatus of another bacteria/no, you failed to account for the proteins in the motor and it appears the type III system came after the flagellum pump etc. That's science.
Can't argue with that even if I am the missing link :-)
You make the assumption that nobody understands this but you and those with whom you agree. Because you dogmatically embrace this theory you fail to see the flaws in its claim that life came from a single source and evolved to its present state without direction, and ridicule -- I'll repeat ridicule -- those who question it.
Now Dembski's ID & Behe's IC refute it. Whether they "disprove" it, I'll leave to a debate on semantics for another time.
Hey, Happy Darwin Day everybody.
ID is not math based. It is scam based.
ID is creation science with a new name and an improved sophistry.
You can't "dogmatically" embrace a scientific theory.
Scientific theories are based on interlocking data, with no data outside the theory that would refute it.
ID is dogma because it is not a scientific theory, it is a set of beliefs based on Biblical misinterpretation and wrong-headed thinking.
The eqivalency that you attempt to pawn off between understanding science and idolatrous superstition is the same as the communists tried to say about democracy and their bankrupt system. It is reprehensible that you would even suggest that Behe is equivalent to Darwin.
"life came from a single source and evolved to its present state without direction"
You reveal your creationist misunderstandings every time you post something like this. The direction of evolution is toward survival.
"I'm not sure what you mean by creatiionism. For instance, ID is not Biblical literalism."
Sure.... ID is not science. It is disguised literalism since creation science was disgraced.
You have dogmatically embraced evolution -- now that may be because it has gone beyond science. Or, more likely, it's because your precept is incorrect.
"You have dogmatically embraced evolution -- now that may be because it has gone beyond science. "
No matter how often you put up that canard, it is not true.
I base my understanding of evolution on the scientific data and evidence that I have analyzed over the past 40 years.
Your perception that science is the same as nonsense and philosphical masturbation of ID and IC is totally because YOU are biased and unwilling to do the hard work necessary to understand the science.
there is such a thing?
The same would hold true if I were to edit my orginal post which was:
There may be some people who are put off for a time by apparently uneducated and unscientific Christians.
like this:
There may be some people who are put off for a time by apparently arrogant scientists.
In both cases, I am suggesting that these are stumbling blocks to winning converts to your viewpoints.
I fully agree with the above statements. With the caveat that the Nicene Creed does not include any positional statements regarding the age of the earth or the manner in which life appeared upon the earth. Insisting that one take a position for or against either is contrary to (what I believe is) one of the goals of the Creed which is unifying the church. This is why I have tried to explain in this thread that this issue is not so important as to cause so much contention, particularly among professed Christians.
Creationists practice all of the above and by doing so, distort the Gospel.
Perhaps some creationists do as you suggest, but certainly not all, and in my experience, not even most. I suggest that you consider changing your paradigm to include the possibility that people can be sincere, yet wrong. When you suggest that people are lying, you are by definition suggesting that they are KNOWINGLY misleading people. Do you really think that there is such a vast conspiracy among all the Christian Churches in this country who believe that the Bible is inerrant and literal? No, it is not so. The simple fact is, these people truly believe this in their hearts to be true.
There are certainly exceptions to any generalizations regarding human behavior, but generally, these are well-meaning people. They are arguing for what they believe to be true, they are not attempting to deceive.
I will grant you (probably to the delight of non-Christians on this board, lol) that a lot of Christians who show up here are ill-prepared to discuss science and are in over their head when it comes to reasoning logically. At least, that has been my observation. However, can you not admire their determination to enter the lion's den, so to speak?
Believe it or not, I just happened to stumble upon this thread out of curiosity of the subject matter. I have never visited a "crevo" thread or whatever it is called before this one (to the best of my recollection), and I have been a Freeper since 2000.
There are certainly exceptions to any generalizations regarding human behavior, but generally, these are well-meaning people. They are arguing for what they believe to be true, they are not attempting to deceive.
I would also remind anyone reading this that in all likelihood, the persons you may encounter in these forums are probably NOT a very good representative sample from which to draw conclusions. Many here are probably here because they are looking for a fight. This includes representatives from all sides of the issues.
If we continue to to concentrate on and to reinforce stereotypes of each other, (i.e. all creationists are liars, all Biblical literalists are radical fundamentalists, all Christians are idiots, all evolutionists are atheists, all scientists promote secularism, all non-biblical literalists are evil,) we will never find common ground and will remain at odds with each other.
and I would answer:
again, there is no "may be" about it - nor, in many cases, any "apparently" either.
I would add that the arrogance (or its appearance) of scientists is preferable to the abysmal ignorance AND arrogance of those uneducated (and proud of it) among the religious to whom we both refer.
Humility on both sides would be preferable, of course.
However, please note, even the deepest human humility, patience, and tolerance can be tested beyond its limits by serial willful, disingenuous, and antagonistic stupidity in the face of repeated correction and instruction.
Touche'
"This is why I have tried to explain in this thread that this issue is not so important as to cause so much contention, particularly among professed Christians."
I understand your position and I think you are dead wrong.
It is important to our country that we teach good science in schools. That a certain sect of morons has been duped by charlatans is not a reason to allow the desire for "unity" to hurt our country. In fact, it is evil as far as I am concerned, to spout nonsense and leave children in ignorance due to willful ignorance on the part of adult
semi-Christians.
"The simple fact is, these people truly believe this in their hearts to be true."
Not the creationists who post on these threads. They are willfully ignorant.
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