
As a result of climate change, fish started to enter night mode to protect themselves in the warming waters.
The scientists discovered that the increase in ocean acidification made fish to activate defense mechanisms that are usually used during the night time when the level of carbon dioxide in the water was higher than during the day.
Ocean Acidification
The acidification process involves the immersion of the carbon dioxide produced by burning fossil fuel in the water. When the intensity of the acid reaches a peak, fish adjust their behavior to night mode in order to fight the effects.
While at first the process was thought as a positive one, because it absorbed the carbon dioxide out of the air, the scientists later discovered that the acidic waters could affect chemical communication, dissolve shells, and impair the reproduction process.
Fish Night Mode Protection
The conclusion was the result of studying the spiny damselfish. The Acanthochromis polyacanthus has a life profoundly influenced by a circadian rhythm. The discovery that amazed scientists is that the fish species started to produce offspring that can control their body clock, something that had never been observed before. The fish switched permanently to night mode.
In the experiment, the researchers bred the fish in water containers that had carbon dioxide levels similar to what the Earth could expect in the following years. To determine the reaction to their changing environment, the scientists analyzed the genetic code and the proteins found in the fish brain.
A next direction of the study would be to determine how the genes are passed on from one generation to another.
Adaptation of the Species
The adaptation is seen as a potentially favorable condition for fish, as usually, the marine animals have a hard time coping with acidification.
However, there are other species that can adapt to climate change. For example, the corals are being repopulated by heat-tolerant algae. Scientists just worry that the global warming may be happening too fast for the species to adapt.
The scientists believe that it is unlikely for all the species in an ecosystem to change all at the same time while preserving their present behavior and interactions. The biggest challenge would be the timing of the adaptation process.
The factors that can influence the adaptation are the amount of genetic variation, the generation time of the species, and the capacity to pass the tolerance genes from one generation to another.
Image Source: Wikipedia