The terms “wild” and “feral” get confused – for example, people refer incorrectly to wild horses in North America. The native horse in North America became extinct in the Pleistocene and all horses on the continent today are derived from domesticated horses that were brought over from Eurasia (i.e., they were introduced). Some of those have escaped or been liberated and become feral populations that persist for generations. So we don’t really have wild horses – those natives are long gone – we have feral domesticated horses that were introduced.
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If there wouldn’have been humans, then there wouldn’t have been domestic dogs…
Coevolution in nature, in my opinion, does not well fit as an example with this case
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Any conversation about Canis on the North American continent should be ready to deal with the grey zone in the species definition. The Coyotes around here are mixing with dogs and far from homogenous.
If that’s iNat’s definition of “introduced”, why isn’t Homo sapiens marked as introduced (at least outside of Africa)? Or human-specific parasites such as Pediculus humanus?
There are a few unstated qualifiers, including something similar to “… during recorded history”. For example, the usual cutoff date in the Americas is 1492: if a species was in the Americas before that date, it’s considered native. That obviously includes Homo sapiens and many of our parasites. I’m not sure what the accepted start dates are for other regions of the world.
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@JeremyHussell - That’s exactly why Canis familiaris should not be listed as “introduced” in the United States or Canada. The domesticated dogs that later became the Alaskan Malamutes, Greenland Dogs, and Canadian Eskimo Dogs were introduced to North America by the Thule culture around 1100 AD (according to the most current archaeology). While all the other “native” breeds of domesticated dogs were wiped out by European colonization, those Arctic breeds have survived to the present day. Molecular studies have shown that these breeds are genetically distinct from other North American dogs and are the sister group to the extinct pre-contact breeds. In addition, several other modern breeds are said to have “native” ancestry, such as Chihauhuas and Peruvian Hairless Dogs, although the genetic evidence is inconclusive.
I don’t think self-introduction counts in terms of what we mean when we say a species is introduced. Humans got to where they are by their own means (I’m not going to touch the subject of slavery) and not due to the intervention of another species. The species-specific parasites they brought with them were just along for the ride. The geographic range of a parasite is typically considered as the geographic range of the host since the host is its habitat.
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First you say that “introduced” means “Arrived in the region via anthropogenic means”, but apparently that isn’t true. Then you say that “introduced” means “Arrived in the region via anthropogenic means during recorded history”, but apparently that isn’t true either. Now you say that “introduced” means “Arrived in the region via anthropogenic means, unless they were self-introduced or ‘just along for the ride’”. But lots of introduced species were ‘just along for the ride’: snakes in Guam, Norway rats in New Zealand, Zebra Mussels in the United States. None of these species were introduced on purpose.
It’s strange to me that y’all seem to be bending-over backwards to erase the fact that domesticated dogs were in the Americas long before Europeans arrived.
The 1492 cutoff is not really appropriate for introductions in the New World. It’s just that the majority of introductions occurred since the start of European colonization. There really isn’t some time limit associated with when Homo sapiens introduced another species.
By “along for the ride” I mean literally. Parasites ride on or in their hosts. Quite different from an organism that is carried in or on a vehicle or in cargo. I’m pretty sure Zebra Mussels don’t stick to people.
@jnstuart - So would you say that dog fleas (or any other domestic dog parasites) are native or introduced to the United States? (A better example might be Dictyocaulus arnfieldi, the horse lungworm, as it almost certainly arrived in the Americas with the introduction of horses.)
Hypothetically, if a parasite is host-specific and the evidence indicates that it did not occur in the New World until it rode over in association with an introduced domesticated animal species as its host, then it too is introduced. A second-hand introduction. However that evidence for or against it being a non-native might not be available or ambiguous in some cases.
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There you go.
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I don’t really understand the point of this debate/questioning of the “introduced” definition. It seems like it has devolved past confusion over the term into intentionally trying to poke holes in the concept.
Like any either/or classification we apply to the natural world, there will always be some edge cases or difficult to classify situations. The real world is more often gray than black or white. That doesn’t negate the utility of having a simple binary classification for whether a taxa is introduced to a given region.
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I’m just trying to find out what the actual definition of “introduced” is on iNaturalist, as there seems to be a lot of inconsistency and disagreement, especially related to domesticated taxons. One way to do that is by exploring edge cases and current inconsistencies. For example, we currently classify the domestic dog and domestic cat as “introduced” pretty much everywhere, but we don’t do that for other domesticated animals like domestic turkeys (which are listed as native in the U.S.). How should domesticated animals be handled?
- Domesticated taxons should be listed as “introduced” everywhere (since every individual is where it is because of humans).
- Domesticated taxons should be listed as “introduced” everywhere, except for their original location of domestication, if known.
- Domesticated taxons should be listed as “introduced” everywhere, except for locations where the equivalent wild taxon is native.
- Domesticated taxons should never be listed as “introduced”, since they are domestic and not part of the wild fauna (i.e. they are exempted just like humans and other human-associated organisms).
Could we have a vote on which of these rules to apply?
I agree.
Turkeys occur in both the wild native state (never domesticated) and as domesticated in North America. I don’t think iNat distinguishes but maybe it should.
iNat has a separate taxon for domestic turkeys: https://www.inaturalist.org/taxa/524794-Meleagris-gallopavo-domesticus
Cool. Now we can debate whether a domesticated form of a wild species should be recognized taxonomically as a subspecies (I think it should not). But that’s another discussion. ;-)
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@zygy the definition for introduced establishment means on iNaturalist is a taxon that “arrived in the region via anthropogenic means”. This definition derives from DarwinCore and is part of the standardized vocabulary in biodiversity informatics. iNat takes no unique deviation from this useage and is neutral in that regard.
Because this definition specifically applies to establishment means, it is suppose to contrast the definition for “native”, which is a taxon that “evolved in this region or arrived by non-anthropogenic means”. The definitions for “native” and “introduced” are very cut-and-dry. If a dog is in North America, it is because people brought it there. Same with the dog flea, horse, cattle, etc. And I discourage anyone from glorifying individual dog breeds as evoluionarily significant units, for while there are breeds of dog that first appeared in North America, the species Canis familiaris was brought there by humans and did not occur there beforehand. It does not matter how it was bred after the fact.
iNaturalist takes a very neutral position with the application of these terms. I think your dissatisfaction is that these terms are not universally applied to all domestic taxa on iNaturalist, but that has nothing to do with the terms themselves. I think this is because iNat users - as in people, who are busy and have their own lives - have not had the time to setup establishment means for all taxa.
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Well that sounds reasonable to me. In my opinion dogs evolved somewhere on earth so they should be native somewhere on earth. It seems however they are here in iNat classified as introduced everywhere. Same issue with cats (are they really introduced in Egypt?), cattle, zebu (are they really introduced in India?), sheep, goats, lamas and alpacas.
I would vote for this … the taxonomic treatment of domesticated animals and plants seems rather arbitrary, and should have no influence on the “native” or “introduced” status of the respective evolutionary lines. …