image: Three anemone fish at home, Raja Ampat, Indonesia. Image by Mark J. Costello. view more
Credit: Image credit: Mark J. Costello.
A study reports a dip in marine biodiversity at the equator. The latitudinal gradient in marine species richness, in which the tropics host the most species and richness decreases with increasing latitude, is assumed to be stable. Chhaya Chaudhary and colleagues examined distribution data for 48,661 marine species since 1955 to assess the impact of climate change on the latitudinal gradient. The data confirm a recently observed dip in species richness around the equator. Since the 1970s, the authors found, species richness has shifted poleward in the northern hemisphere, with the decrease in species richness at the equator occurring in relation to an increase at midlatitudes, particularly among open-water pelagic species. Such a dip in equatorial biodiversity due to climate change is expected in light of losses of equatorial diversity observed in the fossil record during the Pleistocene and Triassic in response to warming. The results also showed that species richness plateaus or declines above a mean annual sea surface temperature of 20 °C. According to the authors, the results suggest that ocean warming has already created conditions that are inhospitable for some species.
###
Article #20-15094:
"Global warming is causing a more pronounced dip in marine species richness around the equator," by Chhaya Chaudhary, Anthony J. Richardson, David S. Schoeman, and Mark J. Costello.
MEDIA CONTACTS:
Chhaya Chaudhary,
University of Auckland, NEW ZEALAND;
tel: +49 152 07665246;
email: <ccha961@aucklanduni.ac.nz>;
Mark Costello,
Nord University, Bodø, NORWAY;
email: <mark.j.costello@nord.no>