Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5

Atlantic salmon evolving, not growing as big -- not clear why it's probably our fault

#1
C C Offline
https://www.forbes.com/sites/michaelmars...our-fault/

EXCERPT: ... The results have been published in Nature Ecology & Evolution.

[...] Atlantic salmon are evolving rapidly, and the result is they are not growing as large as they used to. The effect has been traced to a single gene. Atlantic salmon (Salmo salar) hatch in rivers in Europe, where they spend their first few years before heading out to sea. Once they reach maturity, they return to their home river to breed.

[...] When to spawn is a trade-off: a salmon that waits longer will grow larger and probably have more offspring, but it also risks dying before it can spawn at all. Primmer's team has found that the salmon are spending less time at sea growing, and instead heading back to their rivers to spawn sooner.

It is not clear why the salmon are evolving to be smaller at maturity. It could be that they are being affected by climate change in some way, or that fishing fleets have targeted the larger individuals, or something else entirely.

It would be misleading to say that the salmon's evolution is a good or bad thing. On the one hand, it suggests that they are adapting to the pressure they are experiencing, whatever it is, which seems encouraging. But it also makes clear that they are under some sort of pressure, and since we do not know what it is, we do not know how much they can endure.

According to the International Union for Conservation of Nature, Atlantic salmon are "least concern", meaning they are not at imminent risk of extinction. However, the species has not been assessed since 1996, so a second look might well revise that finding. Certainly, some of the local populations have declined steeply in recent decades....

MORE: https://www.forbes.com/sites/michaelmars...our-fault/
Reply


Possibly Related Threads…
Thread Author Replies Views Last Post
  Research Flowers ‘giving up’ on scarce insects and evolving to self-pollinate, say scientists C C 0 103 Dec 27, 2023 06:38 PM
Last Post: C C
  Humans are evolving a new artery C C 4 137 Jul 28, 2022 12:20 AM
Last Post: Zinjanthropos
  Vitamin K2 repairs nerve cells + 10 strangest things found growing inside human body C C 0 75 Apr 15, 2022 05:57 PM
Last Post: C C
  Elephants evolving to be tuskless Magical Realist 6 164 Oct 28, 2021 06:56 PM
Last Post: Zinjanthropos
  Just to be Clear on the Distinction Yazata 0 155 Aug 5, 2019 10:22 PM
Last Post: Yazata
  Bland tomato? It probably doesn't have tasty genes C C 4 797 Jan 30, 2017 08:42 PM
Last Post: C C
  Are elephants evolving without tusks? + Hollywood's implausible alien ecosystems C C 1 573 Dec 6, 2016 02:13 AM
Last Post: Syne
  How much is a Brit really Brit? + Growing organs on apples + Antibiotic from noses C C 0 473 Jul 29, 2016 06:09 AM
Last Post: C C
  Why does our food taste like cardboard? + Dodo not so stupid after all C C 0 454 Feb 24, 2016 08:25 PM
Last Post: C C
  Growing other species' brains on a flatworm elte 1 466 Nov 29, 2015 09:16 AM
Last Post: C C



Users browsing this thread: 1 Guest(s)