Ais: Survivors of the Sixth Extinction: The Many-Finned Dolphin

Wednesday, June 15, 2011

The Many-Finned Dolphin

Cetaceans are undoubtedly the strangest of mammals, and I don't find an extra dorsal fin or 'anal fin' to be all that improbable compared with, say, the Sperm Whale's nose, the Narwhal's tusk, or Odobenocetops in general. An extra dorsal fin is not without precedent thanks to the Cornish Bottlenose Snooky, and there have been other sightings of supernumerarily-finned cetaceans, some of which reportedly looked quite unlike known species (see Raynal and Sylvestre (1991) for a review). Rather than a surviving cryptid, the speculative dolphin above is a descendant from a Lagenorhynchus species (maybe L. albirostris or L. acutus) which has taken its thunniform body shape to new extremes. The coloration and shapes of the head and foreflipper are the result of blending together a few Lagenorhynchus species, however the body shape is inspired by Dall's Porpoise, Pilot Whales, Eastern Spinner Dolphin, and scombrid fishes. The general working theory here is that since since the keels already resemble low dorsal fins in some cases, perhaps with some selection they could develop into proper fins.

This is of course not a final draft and could be subject to major change - I could see the extra fin forming separately from a keel (probably losing the 'anal fin'), the males exhibiting a forward-canting (first) dorsal fin like Dall's Porpoise and the Spinner Dolphin, sexual dimorphism resulting in other changes in fin shape and coloration, and a shifting phylogenetic identity. At any rate, there's still going to be an extra-finned cetacean in this final project, and it may very well not be the strangest cetacean out there.

1 comment:

AnonymousNovember 4, 2011 at 9:57 AM
Not to put a damper on your project, but it appears that the dual-finned bottlenosed dolphin "Snooky" is actually an April Fools Joke. The article itself was posted the day before April Fools 2010, and there seems to be no other mention of this two-finned dolphin. Additionally, the article says that Snooky is the result of Lamarckian evolution, where aquired characteristics like injuries are passed down to offspring. This also suggests it was a gag article, as Lamarckism was disproven a long time ago. Finally, the picture of Snooky leaping looks like it has been photoshopped.
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What is Ais?

The Ais project speculates on a far-future scenario where Homo sapiens is mysteriously absent, yet its influence is still apparent. After the largest metropolises have been relegated to buried artifacts and disrupted natural processes have been normalized, the biogeography of the planet remains permanently and radically altered. The Sixth Extinction, second only to the End Permian in intensity, caused numerous major groups to become either extinct or degraded to relicts. The transport of other species by H. sapiens, both willing and not, resulted in the Great Global Interchange, where species became established in regions they had little chance of reaching otherwise. This is a world where continents can have a handful of amphibians species, where Asia appears to only have turtles descended from the Red-Eared Slider, and where cichlids and loricariid catfishes often dominate local waterways worldwide.

As for Ais itself, it is the name of an island, archipelago, and surrounding mainland region which was subjected to particularly extreme human introductions - the now-inundated peninsular Florida. With its near-tropical latitude and newly-rerouted cold ocean currents, it offers almost unparalleled biodiversity and biomass. The numerous small islands and influx of species to and from the mainland make this a 'natural laboratory' comparable to the Galápagos or Trinidad.

The purpose of this project, aside from speculation, is to give commentary on the changes our species has caused. Additionally, many of our creations will not have completely made-up morphology, but emphasize just how strange they already are. Truly, one cannot invent things stranger then reality when one looks closely. This website is a collection of concepts which may not represent our final thoughts on some subjects, which we hope to some day have in book form.