5. Shark diversity can be tracked just from DNA they leave in the environment.
While environmental DNA has been applied to marine fishes before, this study by Bakker and friends shows how incredibly this method can be for studying hard-to-find shark species.
From Bakker and Friends. Bar plot showing the relative abundances of reads (fourth-root transformed) for every elasmobranch MOTU detected in the Caribbean and New Caledonian locations.
6. Sharks eat alligators, and are eaten by alligators.
This paper by Nifong and friendswas the most-covered shark research news story of 2017. It describes what’s called “intraguild predation,” when two (or more) predators species that are at approximately the same level in the food chain eat each other, between alligators and four species of sharks and rays.
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