Animals adapt to their environment. The spotted hyena is the most flexible of all, researchers write in Science

It appears that wild animals can adapt to changes in their environment faster than scientists previously thought. This is what biologists write in Science.

Moths that change color within a few decades and elephants whose females suddenly no longer have tusks. Major evolutionary changes usually take thousands of years, but sometimes they happen at lightning speed.

Before the Industrial Revolution in England, the pepper and salt moths on the island were light in color. But after the soot in the air blackened trees and buildings, more and more black specimens appeared. At any one time the majority of the population was black. The darker the animals were more camouflaged and therefore better chances of survival.

Toothless elephants

Elephants in Gorongosa National Park in Mozambique have also quickly adapted to a change in their environment: increased hunting by poachers. Females who do not have ivory calyx have a better chance of survival, so a large percentage of female elephants in the park are now born without tusks. Usually these animals are very rare. It is estimated that 2 to 6 percent of adult females in Africa do not have large tusks. In Gorongosa National Park 30 percent.

The scientific literature abounds with such examples. Genetic variation within a population causes some individuals to look slightly different from the rest, or to act out of line. Often this is unfavorable, but let the environment change in their favour and misfits will take the upper hand because they suddenly have better chances of survival and can give birth to more offspring. However, despite the numerous examples, little is known about the short-term adaptability of animals.

A study published last week in the journal Science aims to change that. Research so far has focused on the adaptability that animal species owe to genes associated with certain characteristics, such as color or size. But what adaptability is there in the total DNA of an animal species, in the totality of its genetic material? That is the question that a large team of scientists led by evolutionary biologist Timothy Bonet of the Australian National University set out to answer. The answer is a bit ambiguous. They found that “adaptive evolution” was 18.5 percent.

Scientists have had to calculate for a long time. “I think we’ve been busy with these calculations for three years,” says Marcel Visser, one of the authors, bird researcher and senior expert on nipple, Marcel Visser, of the Netherlands Institute of Ecology.

Their number is no joke. According to Visser, the 18.5 percent should be considered as a kind of “evolution fuel” measure. The percentage is two to four times higher than what scientists expected. This is good news. He suggests that animal species may be able to adapt faster and easier – for example to changes in their environment due to climate change – than previously thought.

2.6 million hours of field studies

The researchers didn’t take it overnight. They studied data collected over the past decades during 2.6 million hours of field studies, recorded in 19 scientific publications. Those studies focused on fifteen species of mammals and birds, including the great tits of the Netherlands, the spotted hyenas of Tanzania, and the red deer of Scotland. Some of these studies have been going on since the 1950s.

The researchers found the most “fuel” in spotted hyenas. Biologists from the Leibniz-Institut für Zoo- und Wildtierforschung have been studying animals for nearly thirty years.

“Spotted hyenas can live in all kinds of habitats and are the most widespread carnivorous animal in Africa,” says Oliver Honer of Leibniz-IZW. “This suggests that they can adapt well to new environments, but we did not expect them to have the highest degrees of adaptive evolution of any species studied.”

You need a massive amount of data to set up a comprehensive study like the one in science, Visser says. The Germans analyzed the DNA and mapped the family trees of more than 2,000 hyenas spanning eight generations. ,, You must have the pedigree of each individual. You need to know which animal gave birth to offspring and how many. Few of the studies were accurate enough.” The nineteen studies on fifteen animal species the team examined included data from 250,000 animals in total.

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