"Missing Link" Found!

[xssve]

We're easy to please. Men just have a hard time figuring such things out. 4 million years later, and nothing's changed

For the record, though, I don't agree with the premise that we went bipedal because the men needed to haul food in their arms to get the females to have sex with them. Granted, humans are scavengers and being able to haul food helps us survive better than if we were hanging from trees (that's the deal here right? The hands aren't good for hanging from trees, but they are good for carrying food if bipedal). First, I don't see that sex has to be the reason why we hauled in food--shouldn't it be the other way around evolutionarily speaking? This mutation happens and the animals with it can haul more food so they produce more kids because they're better nourished.

Next, if the "ape" with this mutation can run with a baby in its arms faster from predators, then why wouldn't that be reason enough for it to succeed?

An equally robust hypothesis - not enough information, i.e., environmental conditions.

If, for example, more or better food is available on the ground, but it's safer to eat it in the trees, then it's likely that being able to carry more would be an advantage, you wouldn't have to hit the ground as often - though, in fact, this is pretty much what Chimpanzee's do already, without these particular adaptations - the difference being they rarely venture far from the trees.

The partial bipedalism suggests that Ardipithecus may have had to travel considerable distances from from cover, and that would explain these particular adaptations.

Still, food sharing remains a significant stressor, it's practically unique among humans as a normative behavior, but it may have more to do with extended gestation/infancy - the result of sex, rather than obtaining sex in the first place.

Bit of a resurrection of the old Hunting Hypothesis.

 

[3113]

Still, food sharing remains a significant stressor, it's practically unique among humans as a normative behavior, but it may have more to do with extended gestation/infancy - the result of sex, rather than obtaining sex in the first place.

Bit of a resurrection of the old Hunting Hypothesis.

I'm in agreement with that. It's always made sense to me that if your child is going to take years till it's able to manage on its own (three at least), then one parent needs to watch over it while the other goes off and brings back enough food for all of them. In which case being able to carry food while walking would be very useful. And going distances to find more food, to maybe scavenge meat from predatory kills, would be very useful.

Likewise, this wrist mutation (not able to hang from trees) likely made it harder for children to cling to mom as baby monkeys do to their mothers. So, again, mom may have had to carry the child which interferes with climbing trees and plucking food--hard to do both when you've got a baby cradled in one arm.

 

[xssve]

Good point.

 

[xssve]

Or point's

Here's a viable candidate for a common ancestor, or something similar.


Research team finds first evolutionary branching for bilateral animals

PROVIDENCE, R.I. [Brown University] — When it comes to understanding a critical junction in animal evolution, some short, simple flatworms have been a real thorn in scientists' sides. Specialists have jousted over the proper taxonomic placement of a group of worms called Acoelomorpha. This collection of worms, which comprises roughly 350 species, is part of a much larger group called bilateral animals, organisms that have symmetrical body forms, including humans, insects and worms. The question about acoelomorpha, was: Where do they fit in?

To scientists, acoelomorpha, has been enigmatic, a "rogue animal," said Casey Dunn, an evolutionary biologist at Brown University. "It has been wandering throughout the animal tree of life."

The worm wanders no more. Through a laborious genetic sequencing analysis, Dunn and an international team of scientists have settled the long-standing debate and determined that acoelomorpha belongs as a sister clade to other bilateral animals. The finding is significant, Dunn said, because it shows the worm is a product of the deepest split within the bilateral animals, the first evolutionary divergence within the group. Because of that, scientists have gained a key insight into the most recent common ancestor to bilaterians, a species that remains unknown.

The worm is "as distant as an animal can be in bilateria and still be a bilaterian," said Dunn, assistant professor of biology. "So, now we have two perspectives to (find out about) this common ancestor, the acoelomorphs and all the other bilateral animals."

This guy has a bigger problem with comma splices than I do, and that's saying something.

 

[penandpaper]

It's a fact. They tested the moon rock and found the same minerals and other elements present on Earth. NG had a special on a few months ago about it. There was definitive proof establishing it. The speculative part was the theory of the asteroid they knew hit Earth, but was it the rebound off of Mars, that has markings of a hit from a large object on the surface of it. Just the evidence they've gathered so far from the surface of Mars has been leading them to this conclusion. If a species of humanoid people lived on the surface when it hit, could their DNA have come here on it and grown in the primordial soup, to become us. Just speculation still, but the possibilty of us all being alien beings from another planet might be a proven fact someday.

Lance,

As much as I love science and place much belief in it - this is still a theory. It is being peer-reviewed as we speak. I for one, think it's true. But, I think it's prudent to wait for a little more confirmation than one team of scientists. (Which, if memory serves me correctly numbered three or four.)

 

[Katyusha]

The ALH rocks? Those were proven, disproven, then proven again, and again disproven. There's no consensus there.

Like I said, last thing I heard about that.

 

[Katyusha]

Bolded the dangerous bit. While it is indeed a theory concerning a large impact early in earth's history leading to the formation of the moon, you can't say 'just'. That is sloppy thinking.

A scientific theory is an idea that has been tested repeatedly and supported by reasonable amounts of data. In short, it is the best explanation we have that fits observation and experimentation, and has not yet been disproven by any means. It may be disproven in the future, but until then it is the best we have. Essentially, a "theory" in science is as close to claiming 'my idea is right' as any scientist will comfortably get. Its kind of a big deal.

The way you used 'theory', it should be replaced by 'hypothesis'. Even though the earth-moon thing is actually a theory.

Pardon me and my sloppy wording.