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Researchers confirm that narwhals and belugas can interbreed

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Re: Researchers confirm that narwhals and belugas can interbreed

#21

Post by k_sze »

k_sze wrote: post #20

One thing I’m curious about is how the researchers even tell that the hybrid is a bottom dweller. They have only seen the skull, not what was inside the hybrid’s stomach. Can some biologist shed some light here?

So I was still thinking about this question while taking a shower. Did the researchers come to that conclusion by analyzing food stuff that was still lodged in the jaws?

Oops, upon rereading, I just spotted “isotope analysis”. How different are isotopes between water-column diet and bottom diet?

Re: Researchers confirm that narwhals and belugas can interbreed

#26

Post by SkyBelow »

paulmd wrote: post #12
kijin wrote: post #11

Huh, narwhals and belugas aren't even in the same genus. Most well-known hybrids like tigers and lions, horses and donkeys, and tomatoes and potatoes have been between species in the same genus. Maybe this discovery will prompt biologists to place narwhals and belugas in the same genus? It must be lonely being the sole member of a genus, after all.

by a strict definition of species, this means they are in fact the same species.

I'm not sure there is a strict definition of species. Take a ring species where A and B can interbreed and B and C can interbreed but A and C cannot. If some event kills all the B's, then you have two species instead of one. That you can make new species by killing only seems quite odd.

Re: Researchers confirm that narwhals and belugas can interbreed

#27

Post by inflatableDodo »

paulmd wrote: post #12
kijin wrote: post #11

Huh, narwhals and belugas aren't even in the same genus. Most well-known hybrids like tigers and lions, horses and donkeys, and tomatoes and potatoes have been between species in the same genus. Maybe this discovery will prompt biologists to place narwhals and belugas in the same genus? It must be lonely being the sole member of a genus, after all.

by a strict definition of species, this means they are in fact the same species.

We don't really have a strict definition of species. It is notoriously hard to pin down.

Re: Researchers confirm that narwhals and belugas can interbreed

#28

Post by undersuit »

k_sze wrote: post #20

One thing I’m curious about is how the researchers even tell that the hybrid is a bottom dweller. They have only seen the skull, not what was inside the hybrid’s stomach. Can some biologist shed some light here?

This is super interesting: "We observed a general increase in sterol δ13C signatures with depth, which is likely related to a combination of particle size effects, selective feeding on larger cells by zooplankton, and growth rate related effects"

https://www.biogeosciences.net/10/2787/2013/bg-10-2787-2013....

Carbon-14 is created in the atmosphere where it is C02 and photosynthetic organisms convert it to more complicated organic compounds. The rate of diffusion of the Carbon-14 through the water column is measurable.

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