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September 19

Does the Southern black rhinoceros still exist?

While reverting an IP who has removed the infobox image from Southern black rhinoceros twice now, I realized this second time that the image was taken in 2022, despite the page saying Diceros bicornis ssp. bicornis went extinct in 1850. The image is sourced to iNaturalist, which has many more recent photos and sightings.

IUCN lists it as near threatened, not extinct, and this 2011 paper indicates it is still extant. From a quick skim, the citation at the end of "This former species was brought to extinction ..." in the introduction says, "The genus contains one extant species, D. bicornis", with nothing specific about the subspecies.

However, there is an "IUCN status" section on this page (as well as South-western black rhinoceros), added by @J. J. Hornung in 2012, that claims the IUCN confused it with D. bicornis occidentalis. Neither the IUCN nor Pachyderm journals cited mention such a subspecies, but I know very little about biology, so I don't feel qualified to definitively change the article. Can someone help clarify what's going on here? Iiii I I I (talk) 17:53, 19 September 2026 (UTC)

The article states "Zoos, animal sanctuaries and conservation centers use this same scientific name as an indicating reference to the surviving south-central black rhinoceros." Which means the website is referencing the wrong Wikipedia page... assuming our articles are accurate. There should be no photo. Modocc (talk) 00:38, 20 September 2026 (UTC)

Thanks for taking a look. Which article are you referring to with that quote? Iiii I I I (talk) 18:29, 20 September 2026 (UTC)

South-central black rhinoceros. Modocc (talk) 18:36, 20 September 2026 (UTC)

Ah okay, I thought you meant one of the journal articles cited on the page. How do you know this is correct, though? It was added by an IP without a reference, and it contradicts the IUCN status section, which mentions D. bicornis occidentalis, not D. bicornis minor. Iiii I I I (talk) 18:42, 20 September 2026 (UTC)

I don't know if it is correct or the only one. However, black rhinoceros lists the extant subspecies and the extinct southern black rhinoceros which this article covers in detail. Modocc (talk) 19:08, 20 September 2026 (UTC)

Also the south-western black rhinoceros article asserts: "This subspecies is often mistaken for either the extinct southern black rhinoceros (D. b. bicornis) or the southeastern subspecies (D. b. minor)." Modocc (talk) 01:35, 21 September 2026 (UTC)

We can't say that a subspecies "went extinct in 1850" when we do not even have one source that says it is extinct at all. Unless there are sources that says they went extinct that information should be removed. And to avoid citogenesis danger it must be an RS dated before that was put in the WP article. HierophantOfOmens (talk) 18:12, 22 September 2026 (UTC)

I've removed the photo that was recently added about three weeks ago. Modocc (talk) 00:57, 20 September 2026 (UTC)

September 20

Extraterrestrial ice halos

What would ice halos around the sun look like from other planets? Mars’ would presumably look similar if not exactly the same as ours, but outer planets like Jupiter, Saturn, Uranus, et cetera, have atmospheres with ice crystals of far more interesting compounds than oxygen and CO2; stuff like ammonia and methane. How would that affect the appearance of ice halos? Would there be different arcs? Are there hypothetical images (like ray traced simulations) of these arcs? Do they have names (or would the individual arcs each be analogous to one of our Earth arcs and thus take their names)? Cheers, 𝔰𝔥𝔞𝔡𝔢𝔰𝔱𝔞𝔯 ^{(𝔱𝔞𝔩𝔨)} (any/all) In solidarity. 09:55, 20 September 2026 (UTC)

September 24

Walter Breuning, calorie restriction, and extreme longevity

Is Walter Breuning proof of concept for the idea that calorie restriction can extend human longevity? ~2026-51245-33 (talk) 02:49, 24 September 2026 (UTC)

Is his lifelong love of cigars proof for extending human longevity? ←Baseball Bugs ^{What's up, Doc?} carrots→ 04:15, 24 September 2026 (UTC)

Good genes can sometimes immunize one from the negative health effects of smoking. See Jeanne Calment and her smoking habits. ~2026-51245-33 (talk) 07:41, 24 September 2026 (UTC)

It appears that she did not smoke very much. But good genes have to be considered for contributing to longevity. I am personally aware of individuals who were quite overweight and yet lived to be over 100. ←Baseball Bugs ^{What's up, Doc?} carrots→ 13:02, 24 September 2026 (UTC)

Which people were relatively fat when they were centenarians, other than Leon Kaleta (1912-2022) and Alberto Andrade (1911-2021), both of whom died a month or two before their 110th birthdays? And I suppose Lawrence Brooks (1909-2022) at age 103, based on the photo that I've seen of him at that age from a newspaper article. (Unlike Kaleta and Andrade, who kept their weight until their death, Brooks became much thinner when he reached supercentenarian status.) ~2026-51245-33 (talk) 20:55, 24 September 2026 (UTC)

In the first half of the 20th century, several of the so-called blue zones combined wide-spread poverty (even famine, as in Okinawa) with conditions requiring strenuous physical activity (such as the daily tending to vegetable gardens up in the mountains in order to feed the family). While far from proof, this, as well as published studies on other mammal species, may be stronger indicators than a single data point could ever be. Regular exercise may be part of the mix required for caloric restriction to have a lifespan-extending effect. Without large-scale studies controlling for all kinds of potentially confounding factors, very little can be said with confidence.  ​‑‑Lambiam 07:12, 24 September 2026 (UTC)

There are many (too many) studies on calorie restriction in mice. The consensus is that it increases average and maximum lifespan. It is assumed that the effect translates to humans. ~2026-46630-01 (talk) 13:39, 24 September 2026 (UTC)

Incorrectly assumed. Lifespan can easily be increased in mice, for example by upping expression of superoxide dismutase, but then when you look in humans, they are already running superoxide dismutase on max. Humans are incredibly long-lived given their body mass, indicating lots for natural selection for it. Mice are selected for fast generation time. See Allometry and r/K selection theory. Abductive (reasoning) 17:59, 24 September 2026 (UTC)

One exceptional person isn't proof of anything. I suppose he's proof that calorie restriction doesn't make extended longevity impossible, but beyond that you can't generalise. in solidarity Chuntuk (talk) 12:04, 30 September 2026 (UTC)

September 25

Euacidalia brownsvillea

What does the larva of Euacidalia brownsvillea look like? There is a single observation tagged as larva on iNaturalist but it's not Research Grade, and that identification is based on computer vision (which can't be particularly accurate for the larva of this species if there aren't any other larva observations, since the computer vision model is exclusively based on iNat observations...), so I'm hesitant to make any conclusions from it. I've tried searching everywhere online - TWL, Google Scholar, many many moth websites - but there's not many results, and none with images of larva. The original description of the species may have a description of the larva, but I haven't been able to find it freely online. Suntooooth, it/he (talk | contribs) 20:36, 25 September 2026 (UTC)

Your link works, just have to scroll down to its entry. If that link doesn't work try this one. But it doesn't look like Cassino talks about the larval form. Abductive (reasoning) 23:50, 25 September 2026 (UTC)

The link doesn't work for me, it shows the top of the entry but refuses to show the rest of the page for copyright reasons (even though I'm pretty sure the book would be in the public domain by now...). That's a shame, though. Suntooooth, it/he (talk | contribs) 00:19, 26 September 2026 (UTC)

The description in this source is of adults only.  ​‑‑Lambiam 06:19, 26 September 2026 (UTC)

October 1

Are dyslexia and nonverbal atavisms, and why do/don't they count as such?

Around a year or two ago, I discovered the term "atavism" – the state in which a trait (e.g. a tail or hind limbs) that have been lost through evolutionary pressures reappear in an individual. This made me wonder – can the two aforementioned disabilities count? Goats 601 (talk) 20:29, 1 October 2026 (UTC)

This is a popular pop science topic. Not to say that its wrong. Rick Riordan made Percy Jackson have ADHD and dyslexia for the benefit of his son's self-esteem, and suggested that these are traits and that they would have been adaptive in the past. There is this hypothesis of self-domestication in humans. Certain issues come to mind; there is basically no genetics for these disorders, and natural selection in humans is incredibly weak in general, and in particular for behaviors. The whole field of evolutionary psychology is a scam and a joke. But don't rule out the possibility that some disorders might be atavistic. Just be unbiased. Abductive (reasoning) 00:09, 2 October 2026 (UTC)