An African jackal looks like an American jackal: Canis anthus vs Canis latrans, part 2

@paradoxornithidae @jeremygilmore

...continued from https://www.inaturalist.org/journal/milewski/69855-an-african-jackal-looks-like-an-american-jackal-canis-anthus-vs-canis-latrans-part-1#

There are three broad possibilities, in accounting for the similarity between the North African jackal and the coyote.

1) These are actually the same species, as in the case of the wapiti (Cervus canadensis), but even more disjunct (see https://www.inaturalist.org/journal/milewski/53495-the-wapiti-instant-megafauna-for-america-made-in-china).

The obvious mechanism in this case is a former land-bridge across Beringia

2) The North African jackal and the coyote are evolutionarily convergent species, having been shaped by similar environments despite different ancestry within the genus Canis.

3) The species-concept is invalid in genus Canis, because hybridisation continually prevents speciation in any strict sense. More particularly, both the North African jackal and the coyote are phenotypic rather than genotypic expressions of a genetic pool that alternatively expresses itself as what we call the wolf.

If we lacked evidence of extensive hybridisation within Canis, the most logical approach would seem to be 1).

In that case, we would just declare a single species (as in the wapiti). We would then set about explaining how the species spread so far, and then lost its connection over such a vast gap.

However, it seems certain that hybridisation is important. Nobody can ignore the 'coywolf' in North America (https://en.wikipedia.org/wiki/Coywolf). This is not only a 'new species' appearing in real time, but such a dynamic one that it has invaded cities from one decade to the next.

This seems to rule out 2), because evolutionary convergence is a valid concept only where ancestors are discrete.

What is left?

Seemingly the 'unthinkable': that much of the diversification in Canis is more phenotypic than genotypic, and that populations remain morphologically and ecologically different in different situations mainly because of 'cultural' differences.

Another way of saying this is that differentiation within Canis has been more about 'software' than about 'hardware', as mechanisms of inheritance.

As evidence of the latter, one of the best examples I can offer is the case of the wolf in India (https://www.inaturalist.org/observations?place_id=6681&taxon_id=42048).

It seems inconceivable that the wolf would survive in India to this day, given

• the long-standing pressure on wild canids from the dense population of Homo sapiens in India, and
• the unlimited opportunities for interbreeding with the domestic dog in feral form (plus, of course, the Eurasian jackal).

And yet not only has it done so, but it seems 'purer' there than in e.g. North America, because it lacks the melanistic morph associated with interbreeding with Canis familiaris (https://en.wikipedia.org/wiki/Black_wolf).

How can the continued 'integrity' of the wolf in India not be a result of 'canid culture' rather than merely genetic 'hardwiring'?

Posted on September 11, 2022 08:35 AM by milewski