Are Domestic and Wild Salmon Still the Same Species? | Hacker News Reader

Are Domestic and Wild Salmon Still the Same Species?

nautil.us

21 pointsdnetesn17 comments

tldr; Yes (see second last paragraph).

I suspect if you put some farm salmon back into the wild, they would, some generations later, end up reverting back to thier wild state.

Sure, the title was clickbait. But the concepts in the article are worth talking about: the rapid evolutionary changes to salmon, the first domestication of a carnivorous fish, what it means that fewer and fewer wild animals will be able to escape human impact.

There is a very simple scientific test whether or not two animals are the same species: if they can breed and have fertile offspring they are the same species, otherwise they are not. All the discussions about whether or not they are physically similar to each other are pointless.

This is not the only measure of a species. Please read the article.

It's the least arbitrary and most accepted widely measure, though.

Unfortunately, it is hugely over simplistic. Using it you can conclude that blackberries and raspberries are the same species and that lions and tigers are kinda-sorta the same species, since it has been possible to get Ligers to successfully mate with their parent species.

So regarding its characterisation as "a very simple scientific test" - no, it isn't.

There are even not-uncommon situations where Population A can breed with Population B, and Population B can breed with Population C, but Population A and Population C can't interbreed.

Using "can breed" as the metric for "same species" creates the situation where A and B are the same species, and B and C are the same species, but A and C are not. That's clearly contrary to what most people have in mind when they use the word "species".

Species really should be a continuum rather than a binary.

Polar bears and grizzlies are probably a better example. They produce fertile offspring but no one thinks of them as the same species.

Wolves, coyotes, domestic dogs are another example that comes up in this discussion.

Yeah, all of those can interbreed, more or less. On the other side of the coin, consider dogs alone. Successful breeding between Great Danes and Chihuahuas is quite rare. :-)

The "successful breeding" metric isn't very satisfactory on any level

In high school. Once you take a slightly closer look, it completely fails all over the place (ring species, asexual reproduction, etc etc).

Has Betteridge's law of headlines failed me?

"We now manage salmon’s evolution—even to the point of genetically modifying them to grow faster."

It's not "genetic modification", it's "genetic selection", and that's what humanity has done for all domestics species since the beginning of times.

Actually, they are being genetically modified: https://en.wikipedia.org/wiki/AquAdvantage_salmon

No, it is genetic modification.

Think of it as beauty modification. Breed good looking man, with good looking woman, you select for a good looking child. On the other hand, take an ugly child put it under a knife and through plastic surgery you modify for a beautiful child. That's the difference between genetic modification and genetic selection. Genetic selection has a long history, genetic modification does not.

Your example of plastic surgery is definitively not genetic modification. Just modification.

Yes. It is called an analogy.

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