Why Ocean Parasites Get Worse the Deeper You Go

What the film says

1. The tongue-eating louse, Cymothoa exigua, enters a fish through the gills as a juvenile male and later becomes female.

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2. Greenland sharks are the longest-lived known vertebrates, with estimated lifespans of hundreds of years.

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3. Placentonema gigantissima, a nematode of the sperm whale placenta, reaches 8.4 metres (28 ft).

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4. A 2020 Global Change Biology meta-analysis found a 283-fold increase in Anisakis abundance from 1978 to 2015.

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5. A 2023 University of Washington study of Puget Sound fish specimens from 1880–2019 found parasites needing three or more hosts declined about 11% per decade, linked to warming sea temperatures.

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6. The tongue-eating louse destroys a fish's tongue, attaches to the stump and works as a replacement tongue, and it can live up to three years.

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7. A female Sacculina larva finds a joint on a crab's body and molts into a kentrogon, which injects the parasite into the crab.

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8. Anisakis infection can cause symptoms that mimic Crohn's disease.

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