Researchers recently announced they’ve found four new species of “walking shark,” which will help them to understand how the Genus to which the unique sharks belong was able to split off from the rest of the Hemiscylliidae family. But even though these newly discover shark species will probably help to grow our understanding of how nature’s favorite hunting machines speciated over time, it’s still just plain bizarre to watch the walking sharks cruise across coral reefs and ocean floors with their little fin-legs. Also, it’s quite cute.
The four new species of walking shark were found in waters off northern Australia and New Guinea by members of a 12-year study, which was aimed at expanding our knowledge of the rare creatures that have evolved the ability to use their fins as locomotive proto-appendages. The group behind the project was made up of members from multiple government organizations and nonprofits, including Conservation International, The Commonwealth Scientific and Industrial Research Organisation (CSIRO), the Indonesian Institute of Sciences, et al.
The results of the research were published in the journal, Marine & Freshwater Research (via UQ News), and while it’s hard to glean exactly why these new species are so important to study based on the paper’s abstract, there is certainly an opportunity here to better understand how, and why, these walking sharks managed to evolve so quickly—all nine of the discovered walking shark species evolved over the past nine million years, while most other species of shark haven’t evolved nearly as quickly. For reference, there are multiple shark species that have existed for more than a hundred million years.
One of the study’s authors, Gavin Naylor, the Director of the Florida Program for Shark Research at the University of Florida, told National Geographic that these walking shark species inhabit a geographical area that “may be the one place in the world where speciation is still going on for sharks,” and discussed how their environment has managed to create a sort of underwater version of the Galápagos Islands.
Naylor says this is the case because the walking sharks’ environment—currently confined to the tropical waters off Australia, Papua New Guinea, and Indonesia—is especially dynamic; meaning it offers up different niches to which the walking sharks have had to adapt. Because of these niches and the way the walking sharks have speciated to accommodate them, Naylor says this is one place (perhaps the only place?) to “see shark evolution in action.”
Looking forward, it seems the researchers will want to spend a lot more time studying the nine known walking shark species in their natural habitat in order to understand how they went from swimming only, to swimming and tippy tapping. Naylor told National Geographic that this will help to shed light on why some species stay the same over time, while others change rapidly.
What do you think about these various species of walking shark? Can you guess at what they’ll look like a few million years into the future? Let’s create a Galápagos Islands of diverse ideas in the comments!
Feature image: Mark Erdmann
