Malin and coauthors, Drs. Anna Eikeset, Doug McCauley, Jonathan Payne, and Jennifer Sunday, published a paper on April 24th, 2019 on the vulnerability of marine versus terrestrial ectotherms. While the vulnerability of marine and terrestrial fauna have each been studied in isolation, a direct comparison of marine and terrestrial organisms physiological sensitivity to warming has yet to occur.
The team used species’ thermal safety margin (the difference between the hottest temperature that an organism can safely tolerate, and its hottest hourly body temperature when in the coolest part of their environment) as a tool to directly compare ocean and land dwelling species. This metric approximates the amount of additional warming a species can tolerate. They calculated this metric for 88 marine and 299 terrestrial species, and found that marine species are more likely to live close to their upper thermal limit than terrestrial species. Terrestrial species also have greater access to thermal refugia (cooler places found within their habitat), such as shaded or subterranean areas. Both of these factors make marine organisms more sensitive to warming than their terrestrial counterparts.
Additional Press Coverage: