Global Warming Creates Change in Species Interactions

According to a recent study, climate change was found to typically lead to local extinctions and declines by influencing interactions between species, such as reducing prey populations for predators. Little evidence has been found to support declining or extinct species due to direct effects of higher temperatures.

Researchers reviewed 136 studies that suggested climate change was associated with local extinctions or declines, and only seven studies identified the primary cause of extinction. None of these studies showed a straightforward relationship between a local extinction and limited tolerances to high temperature. Most implicated species interactions, such as declines in prey species or increased disease spread, as the proximate cause. Additionally, seven studies of population declines related to recent climate change showed a very similar pattern, as did four studies of declines related to natural climatic oscillations.

The researchers identified a number of factors that are considered to lead to extinction from climate change. Impacts of limited physiological tolerance to changes in temperature and precipitation, climate-related impacts on both beneficial and harmful species, and changes to activity times of interacting species due to changes in different cues such as temperature and photoperiods were found to be the top hypothesized factors.

Following this, seven studies where found in which a specific proximate cause could be attributed to a local extinction associated with climate change. Four of these involved changes in species interactions, including climate-related reductions in food species. Other causes included loss of aquatic habitat for African fish species due to drought, both high and low temperatures in an American mammal, and reduced surface activity during the breeding season due to high temperatures in Mexican lizard species.