Should at Least Make Evolutionists Consider

[Purple Knight]

Question for Debate: Why, and how, does the muntjac deer have only seven pairs of chromosomes?

Please don't look this up, at least until you've considered for a moment how weird this is. Imagine you have 20 pairs of chromosomes, and you have a baby that has sixteen pairs. He shouldn't be able to breed with the rest of your species.

Is this at least weird? A regular deer has around 40-70 chromosomes. Is it at least strange that he can even be alive having lost that much genetic information? One more halving and he'll be a fruit fly (they have 4 pairs).

[Difflugia]

Please don't look this up, at least until you've considered for a moment how weird this is. Imagine you have 20 pairs of chromosomes, and you have a baby that has sixteen pairs. He shouldn't be able to breed with the rest of your species.

Is this at least weird? A regular deer has around 40-70 chromosomes. Is it at least strange that he can even be alive having lost that much genetic information? One more halving and he'll be a fruit fly (they have 4 pairs).

The number of chromosomes and amount of genetic information aren't the same thing. Depending on exact details, people with two chromosomes fused or split can successfully have kids as long as the chromosomes can match up and undergo crossover. It's weird and definitely uncommon, but not unheard of.

Human chromosome 2 is actually the result of the fusion of two chromosomes that are still separate in other great apes, apparently fixed in humans through genetic drift rather than fitness. Chimpanzees have 24 pairs of chromosomes and humans have 23 pairs. At some point during humanity's history, there were proto-humans with 46, 47, and 48 chromosomes in the same population. Since meiosis is already error-prone, anything that makes it more so is deleterious and the population will ultimately fix on 23 or 24 pairs, but as long as the unfused chromosomes can pair up with the fused ones, reproduction is still efficient enough prior to fixation. We fixed on 23, chimpanzees fixed on 24. We therefore have fewer chromosomes than chimpanzees, but not fewer genes across those chromosomes.

[Purple Knight]

We fixed on 23, chimpanzees fixed on 24. We therefore have fewer chromosomes than chimpanzees, but not fewer genes across those chromosomes.

So would you predict that a chimpanzee/human hybrid would be possible and itself reproductively viable?

[Difflugia]

We fixed on 23, chimpanzees fixed on 24. We therefore have fewer chromosomes than chimpanzees, but not fewer genes across those chromosomes.

So would you predict that a chimpanzee/human hybrid would be possible and itself reproductively viable?

Not anymore, but not because of chromosome number. Orangutans and gorillas also have 48 chromosomes, but gorilla-chimpanzee hybrids are equally unlikely.