Climate change has already become a threat for the environment and seems like it will have even more impact to an extent that it is likely to affect the ratio of male-to-female newborns. 

A recent study in Japan found a link between temperature fluctuations and a lower male-to-female sex ratio at birth. The study predicted that more boys will be born in place where temperatures rise and fewer boys in place with other environmental changes like drought or wildfires caused by global warming.

The lead author Misao Fukuda believed the conception of boys is especially vulnerable to external stress factors during pregnancy. Stress coming directly from ‘climate events caused by global warming’ might also affect the sex ratio. Fukuda theorized that the vulnerability of Y-bearing sperm cells, male embryos and/or make fetuses to stress is why ‘subtle significant changes in sex rations’ occur, reported CNN.

The authors observed that after a number of earthquakes over the years in Japan, the proportion of male babies born declines by between 6% and 14% from the year before each disaster. Globally, the newborn sex ratio averages 103 to 106 males born for every 100 females, as per researcher Ray Catalano.

Catalano said that this is a result of the fact that a male infant is a ‘relatively frail organism’. He said, “For every society, for every year, the human being most likely to die [prematurely] is male infants. And that’s true for every society that we have data for.”

Though all the reasons for this male-to-female ratio change are not understood, but scientists believe that boys are biologically weaker and more susceptible to diseases and premature death, leaving the possibility for more male-to-female disparity wide open in the age of climate change.