swansont

Already addressed. It’s about the same for chimpanzees. It’s not the same for humans. But nobody is here has claimed that this is the cause of bipedalism. It was presented to rebut your claim that carrying a club is the only advantage of bipedalism (which was based on your erroneous claim that the only problem was defense)

Doesn’t seem obvious to the person who started the thread.

I don’t recall anyone saying that this is the case. The only one proposing a scenario is the OP, and it involves walking upright so you can carry a club (and insisting this is the only advantage of bipedalism)

Again, we have a claim without evidence. You don’t actually know this. An interesting idea is not evidence, and science requires evidence. One can come up with multiple plausibility arguments for advantages that intelligence brings that do not involve making weapons. e.g. better decision-making on where to sleep (defense against predators) or to look for food (pattern recognition, understanding issues of depletion a region of resources). Strategies about hunting, as with the previously-mentioned herding animals over a cliff. Presenting intelligence as having a single advantage and that advantage as the lone driver of evolution is ridiculous.

Then ask questions about game theory. That's really not what game theory does. https://en.wikipedia.org/wiki/Game_theory "Game theory is the study of mathematical models of strategic interaction in between rational decision-makers.[1] It has applications in all fields of social science, as well as in logic and computer science. Originally, it addressed zero-sum games, in which each participant's gains or losses are exactly balanced by those of the other participants. Today, game theory applies to a wide range of behavioral relations, and is now an umbrella term for the science of logical decision making in humans, animals, and computers." IOW, it's not about strategy or tactics, per se. Football isn't a zero-sum game, and it can't really be boiled down to logical decision-making. That's also not game theory

That's not what you asserted, i.e. the statement "Chimpanzees still live in the jungle and they walk on all fours" is not the same as (or seemingly connected to) "Ancient apes had far less vision than predators" or "when they stood upright, they were only more likely to be found by predators" Further, your observation that chimps use branches as clubs seems to be in contradiction with your premise that you need to walk upright to be able to use a club.

Assertion without evidence. Again.

! Moderator Note Is there any substance to discuss here?

Science must include logic, but logic alone is not science. Survival ≠ evolution These are two separate arguments "Nothing to do with" is not what you proposed. You were arguing that the evolution of humans was solely due to innovation. That it was the driving force.

I am not the one presenting the scenario. I am rebutting the silly claim that the only advantage to walking upright is carrying a club.(and that walking is less efficient than continuing to stay on all fours) Please read the thread

I don’t see where I claimed a future advantage, or that the change was not incremental. Why is this not directed at the OP, who presented the scenario? This contradicted by the Nature paper I cited earlier. And if you can’t see them, but they can still see you? That’s better, somehow?

This does not rebut what I wrote. It's like I am saying "These apples are red!" and you are claiming I'm wrong because they are spherical. Can you actually make an argument that efficient locomotion, by requiring less food, is not an advantage in and of itself (i.e. without bringing other factors into the discussion) when food availability decreases? Same question, only applied to being able to see predators from a distance.

Seeing predators more easily is an advantage the enhances survival probability. Efficient locomotion is an advantage the enhances survival probability.

Blatantly untrue, and evidence has been presented to the contrary.

I don't know how you could think this is a reasonable argument. If food is somewhat scarcer, you have to expend more calories to find food. Energy efficiency of movement could be crucial. If you continually expend more calories than you ingest, you will die. How can you "guarantee survival" if everyone starves?

No, that's not sufficient. Something can provide food, but that does not mean food is not a problem if you have to change the effort required to obtain sufficient food for survival. You can die of malnutrition but still be getting some food. Exactly. They needed to forage over a wider area in order to get the same amount of nutrition. This means there is an advantage to walking upright, which is more energy-efficient. And it has nothing to do with holding a club.

So it seems your contention is that a tree, which is very tall and has lots of surface area (lots of bark, leaves, twigs and fruit/nuts) for the ground space it takes up, contains less food than the equivalent space in the savannah. And I am not convinced that this is true.

I didn’t ask why they didn’t move to an environment into which they did not move. You claimed that in moving to the grassland, food is not a problem. I asked for evidence to support this claim. All you’re doing is making another bald assertion. This isn’t evidence. If they can’t change a lot, how could they eat the different food from the grassland?

You have said that safety is the only problem in moving to the grasslands, and food is not an issue. You need to support that this is true, rather than to claim it. I think it is false. I asked for evidence that food is not a problem, as you have not presented anything to support your contention. Back up your claim. Don't just write the same thing.

Grasslands have fewer trees than forest/jungle, by definition. So why does studiot have to justify this, when you have already set the scenario? Repeating this does not make it true, nor does it address the objections/questions I have raised.

This has nothing to do with archaeology. what is the evidence that the paleontological dates vary widely and are inaccurate? Bollocks Why is it that when you do it, it’s “logic”? (not that there isn’t evidence of the environment; there is. Plus, you stipulated to this already) They don’t eat meat very much. Why are they hunting for their food?

So why would they be stalking prey as soon as they got to the grassland? do they live in the grassland, where bipedalism would be an advantage?

This is science, though. Bipedal walking by humans is much more efficient than either bipedal or quadrupedal locomotion by our close relatives https://www.nature.com/news/2007/070716/full/news070716-2.html As expected, chimps were significantly less efficient at walking than humans, using up 75% more energy, irrespective of whether they were walking on two legs or four. Actual study, actual science. Is this true? Did our ancestors eat grass? Is the edible food density as high in the grassland as it is in the jungle? Can you present evidence to support your claim? Your premise included "The ancient apes mainly feed on plants." So this was presumably the diet they were adapted to as they left the jungle/forest. How hard is it to follow a plant? Are you saying there was an immediate switch from mostly herbivore to mostly carnivore? because that seems to be required by your "logic"

A just-so story is not evidence, and the way you have presented it, the innovation happened with the tree-dwellers. If they have this new innovation, why must they leave the trees? There is at least some evidence that the forests were shrinking at this time, the habitat was becoming drier, and that's what forced hominid populations into the open spaces, for at least part of the time. Walking is more energy efficient, so you can walk to forage for food, and if you have a population living at the edge of a forest they still have the protection of the trees. http://humanorigins.si.edu/research/climate-and-human-evolution/climate-effects-human-evolution

You could post it here, at least the relevant parts (like posting the best argument for a claim. Posting evidence that supports it). As it is, you're making claims, and not backing them up. That makes it indistinguishable from guessing without any basis.