Are we really genetically similar to the paleo men and women? page 3

[Gorbag]

Paleo man was NEVER obese so clearly the way we use grains today is quite different.

Don't be too sure about that! Here Venus from Willendorf, 20.000 AC:

[The Scientist]

I will if there is something I can add to. It seems like al the OP's original questions have been addressed. I'm off now for a date with a bird.

[The Scientist]

Don't be too sure about that! Here Venus from Willendorf, 20.000 AC:

A fertility goddess – the ideal baby maker. Ironic how they idealized fat and probably made all the unlucky thin women feel insecure.

[Gorbag]

A fertility goddess – the ideal baby maker. Ironic how they idealized fat and probably made all the unlucky thin women feel insecure.

Yep, that's Grok's ideal woman, the female standard that every respected woman at the time wanted to look like...

[RichMahogany]

I will if there is something I can add to. It seems like al the OP's original questions have been addressed. I'm off now for a date with a bird.

Scientist -

Thanks for the posts. You said basically what most of us here understand but couldn't have said in a way that was nearly as concise, understandable, or accurate. Hope you enjoyed your avian adventures.

[AlanC]

How much of our DNA do we share with chimps and bonobos?

We're still pretty darn close, after diverging around 5 million years ago.

So we're even closer to our direct ancestors, ya think?



AC

[The Scientist]

How much of our DNA do we share with chimps and bonobos?

We're still pretty darn close, after diverging around 5 million years ago.

So we're even closer to our direct ancestors, ya think?



AC

This is an extremely complicated question. Of course we are more genetically similar to our most recent ancestors (chimps) than any other species, and then come great apes, and then monkeys, and then other mammals etc... The problem is that biologists use similarity across the whole genome, or maybe in a specific set of genes, to judge "genetic similarity". This is great for deciding who is most closely related to whom in evolutionary history, but it doesn't answer questions about physiology. For example:

A single base pair change (1 out of 3,000,000,000!) in the right gene can give you muscular dystrophy, early onset Alzheimer's disease, lactose intolerance, etc,...

On the other hand, there are entire genes that have become mostly obsolete that comprise several thousand base pairs that could be deleted and we probably would not see any effect at all.

This means that looking at genetic similarity can tell us all about our past evolutionary ancestry, but it really can't answer questions about how similar we are to other animals as far as physiology goes, because tiny changes genetically can make big differences physiologically. To answer the physiology questions, there is no way around doing carefully controlled and time consuming experiments. Most of these experiments will probably never be done due to the huge number of questions to answer, and the monetary and man-hour cost of answering them. So... the best we can do is assume that each species is best adapted to the environment that it spent most of its evolutionary time in, and then confirm the big questions for humans through experiment.

[sbhikes]

I think it's curious that to defend both grain eating and vegetarianism people want to reject our genetic similarity with Homo sapiens of 10,000 years ago or so and embrace a genetic similarity to apes and other hominid species that aren't Homo sapiens.

[Dirlot]

So I am actually wrong about grains being introduced in the last 10,000 years. It seems we have been eating grains for 40,000 years

Yes there may be evidence that they ground grains, good source of calories but not a sustainable way to eat. You need close to 70sq ft of modern high yield wheat to make one loaf of bread. If we look at natural grasses I would guess you would need a field between 140-200 sq feet to make one loaf. I can not imagine a hunter gatherer cutting, thrashing and grinding a drive way full of grass everyday to make a loaf of bread....that is not sustainable.

[Leida]

Changes that have made their way into our genome in the last 10,000 years are a different story. For example, the lactose dehydrogenase (LDH) gene, which processes lactose in milk, was selected for expression into adulthood because people in their reproductive years clearly benefited from being able to get more calories from milk they collected from domesticated animals.

So, if the thesis is that the adaptations only develop to the harm that strikes early in life, does that mean that lactose intolerance exhibits its harmful effects earlier in life than the grain intolerance?