Wikipedia:Reference desk/Archives/Science/2021 April 1

= April 1 =

Do people with more Neanderthal DNA look more like Neanderthals?
Remains of people found in Peștera cu Oase who had between 5% to 11% Neanderthal DNA did have Neanderthal features. People today have only about 2% Neanderthal DNA. However, some people have a bit more than others due to statistical fluctuations. Do these people look more like Neanderthals? Also, is it possible to create more Neanderthal-like people by selectively breeding humans with non-overlapping Neanderthal DNA sequences to increase the Neanderthal DNA fraction? Count Iblis (talk) 20:25, 1 April 2021 (UTC)
 * I can think of some members of Congress who already look like they've been back-crossed that way. ←Baseball Bugs What's up, Doc? carrots→ 21:00, 1 April 2021 (UTC)
 * Care to name names? {The poster formerly known as 87.81.230.195} 2.219.35.136 (talk) 20:16, 3 April 2021 (UTC)
 * The task of filling up the blanks, I'd rather leave to you. ←Baseball Bugs What's up, Doc? carrots→ 02:45, 4 April 2021 (UTC)
 * It would be theoretically possible, just as it is possible and has been done with various non-human animals, such as some of the cattle variously bred to resemble their extinct aurochs ancestors. However it would of course be completely unacceptable to current scientific and cultural ethics. I suppose one could posit some fictional future authoritarian society that would countenance it.
 * Humans' lengthy generations compared to most other mammals would make it a very long-term project, so I suspect that our hypothetical unethical scientists would instead use genetic engineering techniques to shorten it.
 * Something to bear in mind is that as yet we have very little understanding of how most known Neanderthal (or Sapiens) DNA variations correlate with known aspects of appearance – research tends to concentrate on low-hanging fruit (like hair colour) or disease-related/immune system matters, and most observable physical characteristics are determined by many genes, not just one. We have no idea (to my understanding) whether any of the allotypes found in modern humans so far identified as Neanderthal correlate to their more obvious known characteristics like receding chins, eyebrow ridges, occipital buns and wide rib cages. {The poster formerly known as 87.81.230.195} 2.219.35.136 (talk) 01:05, 2 April 2021 (UTC)

Animal with one testicle
Is (was) there an animal that normally has (had) one testicle, including transitional species? I learned that Australian lungfish has one lung and some gastropods have a single kidney, so possibly one testicle is also an option (also, it seems unlikely that testicles came about already paired in the course of evolution). 212.180.235.46 (talk) 20:36, 1 April 2021 (UTC)
 * Pairing organs is the default in the Bilateria. Even seastars have paired gonads in each arm. The few taxa that have only one gonad, such as hagfish, nematodes, etc, probably lost them over time. Abductive  (reasoning) 21:51, 1 April 2021 (UTC)
 * Gastropods indeed have only one gonad. Many organs in gastropods are not paired, which is associated with the pronounced asymmetry in their body plan, generated by the process of torsion during development and often also by shell coiling. Jmchutchinson (talk) 13:51, 3 April 2021 (UTC)


 * "Asymmetrical monorchy, or the complete absence of one testis coupled with the presence of its bilateral counterpart, is reported for 174 species of the carabid beetle tribes Abacetini, Harpalini, and Platynini (Insecta: Coleoptera: Carabidae) based on a survey of over 820 species from throughout the family." See here. DuncanHill (talk) 15:46, 3 April 2021 (UTC)
 * Which, to put it in perspective, is fewer than 0.05% of all known beetle species. {The poster formerly known as 87.81.230.195} 2.219.35.136 (talk) 20:15, 3 April 2021 (UTC)
 * some homo sapiens perhaps? -- Jayron 32 13:56, 5 April 2021 (UTC)