Linked Questions

36
votes
2answers
16k views

Are there any non-mammalian species known that lactate?

Are there any non-mammalian animals that produce milk to feed their young, or are mammals the only milk-producing animals?
25
votes
2answers
589 views

Can an adult without genetic lactase persistence still develop a tolerance for dairy foods?

While investigating the rise of adult lactose tolerance, I came across the news that China has been encouraging its citizens to drink more milk, even though most of the Asian population lacks the SNP (...
20
votes
2answers
2k views

What inactivates pepsin in infants?

In infants, rennin helps in digestion of milk. Pepsin is also present in their stomach. Why do infants need rennin for milk digestion, at the first place? Why does pepsin not act on the milk ...
11
votes
3answers
5k views

Do humans produce rennin?

At school, we've been taught that human infants produce rennin/chymosin (which aids in the digestion of milk). More specifically, it is the peptic cells in the stomach which secrete prorennin, the ...
6
votes
3answers
654 views

Can domestic breeding be considered evolution?

Domestic breeding of animals (and plants) by humans seems to match some of the definitions of evolution I have been able to find: "a process that results in heritable changes in a population spread ...
4
votes
1answer
1k views

Is there a formal definition of signature of natural selection?

I’ve searched for a definition of signature of natural selection. Unfortunately, I haven’t found any formal definition of it. The signature of positive selection ...
0
votes
1answer
554 views

Why don't humans typically drink human milk after infancy?

Does any human culture routinely do this? Typically taboos have some evolutionary basis. So what would that be? Does any mammal drink the milk of its own species, besides nursing?
1
vote
4answers
251 views

Has a new functional structure ever been observed arising spontaneously?

Have we ever observed a new functional biological structure arising spontaneously such as a new functional organ (sensory or otherwise. such as tracing some creature in the past few hundred years ...
5
votes
0answers
116 views

How frequent are selective sweeps?

Introduction Selective sweep is the most famous genetic signature of selection. We know of a number of classical examples of selective sweeps, some of them in humans. See the classical example of the ...
3
votes
1answer
72 views

Emergence of novel protein interactions by mutation of amino acids

Are there any examples of proteins that, without coming from a recent duplication event, underwent a mutation(s) that caused it to have a novel interaction with a new ligand, substrate, other protein ...
1
vote
1answer
58 views

Do similar adaptations result in similiar genetic code?

Sometimes organisms within the same species evolve similar adaptations to similar living conditions without interbreeding. Let's say we have two human populations which need to adapt to a colder ...