Update: February 2019
Scientists from the University of East Anglia reported that the heat
negatively affects the reproductive function of men. Among women
similar effect is not observed. Observation results
published in the journal Nature Communications.
Periods of abnormally hot weather are recorded more often, even in
countries with a temperate climate. Such changes have already led to
reduction of many populations. The goal of the scientists was
find out why this is happening and what biological mechanisms
exposed to the adverse effects of climate change.
It turned out that the most sensitive to temperature changes
is sperm (see spermogram results). In the experiment
used small beetle beetles (Tribolium castaneum),
which were divided into 2 groups. One lived in normal, familiar
conditions, and the second 5 days was in conditions of increased
temperature (5-7 ° C more than the optimum). In the next
the experiment evaluated the effect of heat on reproductive function,
sperm condition and offspring.
- After the first heat wave, the number of offspring decreased by 2.
times, and after the second wave almost complete
- The females have no effect on heat, although
sperm that were already in their bodies during the heat,
- The number of sperm decreased by 3/4, lost the ability
sperm move and significantly increased the likelihood
their death before fertilization.
- The number of attempts to fertilize the female also decreased.
This experiment revealed an important factor that
reproductive effects, and find the most likely
explanation of the reduction of various populations in the heat. Scientists
urge to pay attention to the problem of vulnerability to change
climate change and take measures to prevent further
negative environmental impact leading to