Climate change major factor behind stark drop in primate population in Northeast India: CCMB

Apart from climate change, anthropogenic factors, meaning human activities like habitat destruction, pollution, hunting etc, may or may not have played a role in the drop of the population of the primate species

Hyderabad: There is a stark drop in the effective population sizes of nine primate species in Northeast India, a groundbreaking population history study of primate species, led by researchers from Hyderabad-based Centre for Cellular and Molecular Biology (CCMB), indicated.

“The study supports our hypothesis that there is a stark drop in the effective population sizes of all the studied species. Among many other reasons including climate, the drop in population of the primate species could be also related to anthropogenic factors,” the researchers in the study, published in Ecology and Evolution of science journal Online Wiley (February 25, 2025), said.

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Apart from climate change, anthropogenic factors, meaning human activities like habitat destruction, pollution, hunting etc, may or may not have played a role in the drop of the population of the primate species.

Referring to the drop in primate population, the researchers in the study said “This can or cannot be due to anthropogenic factors and this is an avenue which should be explored further with higher resolution analysis”.

Past climate change is one of the important factors influencing primate speciation. Populations of various species could have risen or declined in response to climatic fluctuations. Northeast India harbors a rich diversity of primates, where such fluctuations can be implicated, researchers indicated.

“Through this study, we are able to provide a detailed picture of how past climatic changes have resulted in the present species diversity and this mixture of species have either originated in the region or have dispersed from mainland Southeast Asia. We observe that effective population size has decreased for all the species,” the researchers in the study said.

Recent advances in climate modeling as well as genomic data analysis has paved the way for understanding how species accumulate at a particular geographic region. We utilized these methods to explore the primate diversity in this unique region in relation to past climate change, CCMB researchers pointed out.

The researchers collected blood samples of nine primate species including Macaca arctoides, M. leonine, M. assamensis, M. thibetana, Trachypithecus pileatus, T. phayrei, T. geei, Hoolock hoolock and Nycticebus bengalensis from captive animals in different zoos and rescue centres.