Wikipedia:Reference desk/Archives/Science/2018 December 17

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December 17

Newest species

What is the newest animal species on Earth? Not the most recently discovered, but the most recent species that diverged from another species in the same family? Thank you.    → Michael J Ⓣ Ⓒ Ⓜ 22:43, 17 December 2018 (UTC)

See Species problem. There are many different ways to define what a species is, and there is no precise agreed-upon definition even among biologists. When considering geographically separated populations, deciding when these become separate species is quite arbitrary. Besides that, the genetic makeup of many species has never been studied, so there is also insufficient data to really answer this question. - Lindert (talk) 22:52, 17 December 2018 (UTC)

The 5 entries in the Category:Speciation events may be of interest. As Lindert suggests, our knowledge in this area is limited to what we have observed, which can only be a small fraction of all species that exist, and it can be quite difficult (and take a long time to determine) when studying a hitherto unseen species to determine how long it has existed. There is also the question of whether species created by artificial techniques such as hybridization count or not. {The poster formerly known as 87.81.230.195} 90.217.251.247 (talk) 00:15, 18 December 2018 (UTC)

Indeed, this is true; a hybrid species created by deliberate human action (oranges and grapefruits) might be disqualified, but there are plenty of temporarily deliberate/later reconsidered or accidental hybrid species like killer bees and these little guys. Even within species there can be separate groups whose hybridization causes real-world problems [1]. I do think that the mass extinction that is ongoing, with all its losses to posterity, will not plague people so much as evolution's vengeful creativity. But I can think of at least one more or less "new species" that is not a hybrid (that I know of), that being the mutant strain of Caulerpa taxifolia taking over the oceans. But it is hard to get a new species a brand new name, no matter what! I don't know if it's been thought of by those who do such things. Wnt (talk) 04:13, 18 December 2018 (UTC)

There's some discussion of this in an article on gizmodo.com. Rojomoke (talk) 09:33, 18 December 2018 (UTC)

Ah -- Haplochromine cichlids of Lake Victoria, a favorite example of recent speciation (of real accepted species, that is). I vaguely recall thinking there was still a bit of room for skepticism about "cheating" in the sense that multiple precursor species might have hybridized in the past, leaving the adaptive radiation to progress with some reservoir of pre-made pieces, but it is hard to exclude such things from any speciation event, and I haven't tried to chase down what came out of that idea any time recently. Wnt (talk) 14:16, 18 December 2018 (UTC)

There's also the case of Procambarus virginalis, thought to have formed around 1995: [2]. Not everybody agrees it's a separate species. PiusImpavidus (talk) 15:11, 18 December 2018 (UTC)

There are two new species of American goatsbeards (or salsifies, genus Tragopogon) that sprung into existence in the past century. J2088 (talk) 16:42, 20 December 2018 (UTC)