Fossils Bridge Gap in African Mammal Evolution

Reuters to My Yahoo! ^ | Wed Dec 3, 2003 | Patricia Reaney

[Pharmboy]

LONDON (Reuters) - Fossils discovered in Ethiopia's highlands are a missing piece in the puzzle of how African mammals evolved, a team of international scientists said on Wednesday.

Little is known about what happened to mammals between 24 million to 32 million years ago, when Africa and Arabia were still joined together in a single continent.

But the remains of ancestors of modern-day elephants and other animals, unearthed by the team of U.S. and Ethiopian scientists 27 million years on, provide some answers.

"We show that some of these very primitive forms continue to live through the missing years, and then during that period as well, some new forms evolved -- these would be the ancestors of modern elephants," said Dr John Kappelman, who headed the team.

The find included several types of proboscideans, distant relatives of elephants, and fossils from the arsinoithere, a rhinoceros-like creature that had two huge bony horns on its snout and was about 7 feet high at the shoulder.

"It continues to amaze me that we don't have more from this interval of time. We are talking about an enormous continent," said Kappelman, who is based at the University of Texas at Austin.

Scientists had thought arsinoithere had disappeared much earlier but the discovery showed it managed to survive through the missing years. The fossils from the new species found in Ethiopia are the largest, and at 27 million years old, the youngest discovered so far.

"If this animal was still alive today it would be the central attraction at the zoo," Tab Rasmussen, a paleontologist at Washington University in St Louis, Missouri who worked on the project, said in a statement.

Many of the major fossil finds in Ethiopia are from the Rift Valley. But Kappelman and colleagues in the United States and at Ethiopia's National Science Foundation (news - web sites) and Addis Ababa University concentrated on a different area in the northwestern part of the country.

Using high-resolution satellite images to scour a remote area where others had not looked before, his team found the remains in sedimentary rocks about 6,600 feet above sea level.

[Right Wing Professor]

Now RWP, I didn't say determinism is a bad thing, just that it's not the only thing.

That is true; let me rephrase. The conclusion is that a rational choice is not a free choice. I'm inclined to value highly both freedom and reason, and finding a fundamental contradiction between them disturbs me to the extent that I'm compelled to reconsider my premises.

[PatrickHenry]

You and I were both thinking about boundaries at the same time we were posting! Get out of my head, PatrickHenry.

There is a very strange convergence going on here. I don't mind at all.

[Alamo-Girl]

Thank you for your thoughtful post! To clarify why I said you made Phaedrus' point, I would add a fourth choice.

The possibilities are these:

1. Emotion is not compatible with determinism. Animal 'emotions' bear no relationship to human emotions. Animals are deterministic, humans are not

2. Emotion is not compatible with determinism. Animal 'emotions' are at least partly equivalent to human emotions; neither animals nor humans are deterministic.

3. Emotion is compatible with determinism. Animal 'emotions' are at least partly equivalent to human emotions; the existence of emotions does not bear on the question of whether animals and humans are deterministic.

4. Emotion is determined in both animals and humans.

You choose 3, I choose 2, strong determinists choose 4.

Evidently, Rose thinks Pinker is a strong determinist, a 4 – but evidently Pinker thinks he is a 3.

IMHO, the Pinker premise ”the mind is what the brain does” lands Pinker in the 4 category and Rose is a 3 most likely because he deplores eugenics and loves Marxism.

[Alamo-Girl]

I don't mind either! I was just teasing you...

[general_re]

There have been programs that attempted to work out every possible move and counter-move to the end of the game...

Not that I know of - the number of possible configurations of a chessboard is something like 10¹²⁰, which is far more than can be managed in the available space or time, so the program has to prune the search tree somehow - that's where the "rules of thumb" come in. "Deep Blue", for reference, was capable of evaluating about 200,000,000 positions per second - do the math, and you'll see that the total search space is waaaayyyy out of reach. In such a case, the real trick is in the search algorithm - how "clever" the computer is about finding the best possible moves in a limited time and with limited resources, since it can't examine them all.

If, on the other hand, you want serious complexity, the number of possible moves in Go is said to be 10⁷⁵⁰, which is part of the reason that Go-playing computers, by and large, suck compared to humans - in such a game, the human facility for pattern-matching just blows the brute force of the computer right out of the game.

[Phaedrus]

The conclusion is that a rational choice is not a free choice.

Not my conclusion. Free choices can be both rational and irrational. Most human choices are informed more by emotion than reason. Which is not necessarily a bad thing. Free is free, rational or otherwise.

[Elsie]

I cannot fathom what you guys have on your minds.

Intelligence of the gaps.

---

(In our thinking)

[Phaedrus]

”The mind is what the brain does.”

This is where the Materialist "ends up" but all I see is a set of blinders.

[Elsie]

LOL!!!

[Right Wing Professor]

You're right; I left out the strong determinist standpoint. I agree Pinker would choose 4; I mistakenly reverted to my own agnosticism instead of the devil's (Pinker's) advocate position.

Pinker is at least philosophically coherent. I simply can't understand how a Marxist - who is a materialist almost by definition - could not be a determinist.

[Alamo-Girl]

Most areas of science have some element of unrepeatability. Astronomers, for example, study supernova remnants. You can't repeat a supernova explosion.

So very true. But astronomers have physicists backing them up with experiments, such as on the neutrinos. And the physicists are in turn backed up by the mathematicians.

The archeologist has less backing - dating methods, etc. Ditto for the anthropologists. The evolutionists have something in between with molecular biology, geneticists, etc.

IMHO, there is much more infighting among the archeologists, anthropologists and evolutionists than the astronomers because their alternative theories are difficult to test.

[Alamo-Girl]

I agree! Kudos!

[Elsie]

Your perceived 'need' is not mine, and it's not felt by millions of others.

There was no 'need' of cro-magnon either, but, according to popular theory, we got 'em anyway; and they crowded out the "N" fellows.

---

Now the questions is: who will 'crowd' out whom?

The C's or the E's???

The folks with a GOD or those without?

[Phaedrus]

Pinker is at least philosophically coherent.

Boy, if he is, I sure don't see it.

[Right Wing Professor]

Free choices can be both rational and irrational.

You'll have to explain to me how one can apply reason to two identical problems and come up with two different conclusions. And if there is only one conclusion, how can the choice be free?

[js1138]

True. I believe Deep Thought could see upwards of seven moves ahead, not counting rules-of-thumb. Depending on the state of the game, this could count as seeing to the end. Particularly if you play by the unwritten human rules, where loss of a major piece or loss of position can lead to resignation.

I would argue that humans have a lot of hardwired rules-of-thumb. These account of optical illusions and other perceptual tricks, as well as our propensity to make decisions based on perceptual probabilities rather than mathematically sound probabilities. This list could go on and on.

[Alamo-Girl]

Pinker is at least philosophically coherent. I simply can't understand how a Marxist - who is a materialist almost by definition - could not be a determinist.

I absolutely agree. It is so illogical. Rose is a 4 because he is a Marxist, but he chooses 3 because Marxism doesn't work with 4 (and it authenticates eugenics.)

[js1138]

I thought computers had mastered Othello. Is that Go played on a smaller board? Sorry for the ignorance.

[Phaedrus]

You'll have to explain to me how one can apply reason to two identical problems and come up with two different conclusions.

Words are notoriously slippery things. Math may be viewed as the epitome of the rigidly rational. If two mathematicians disagree, one is right or more right and the other is at least less so. So it is with words IF definitions are carefully drawn. Sad to say, we may need a lawyer.

[Doctor Stochastic]

But even in principle, one cannot predict Brownian motion. Measuring instruments small enough to measure the motion are subject to Brownian motion themselves.

From the point of view of Aristotle's "efficient cause," Brownian motion (or QM) is "uncaused" because no causal "event" preceeds the measured event. However, from the POV of Aristotle's "material cause," both Brownian motion (and QM events) are causal. The events are "caused" by the preceeding state (rather than a preceeding event.) The "material cause" does not rule out a probabilistic cause.

For example, a kaon may becay into two neutral pions or a positive pion and a negative pion. The question: "Why did the neutral pions occur?" can be answered by showing the kaon. The question: "Why did the charged pions occur?" has the same answer. The question: "Why charged rather than neutral?" (or vice versa) cannot be answered (I'm not sure the QM formalism allows it to be asked.) The kaon decays one way or the other at random. There is no possible information about the kaon that can indicate which path is chosen. Material causes do not lead to efficient causes.

All proposed modifications, replacements, foldings, spindlings, mutalations, adaptations, etc. of QM have failed to give an efficient cause to tell which path a kaon may take. One problem with all such approaches is that they are required to reproduce experimental results in other cases.