[ad_1]
VANCOUVER – Swallows develop smaller, more manageable wings to help them avoid buildings and vehicles.
Some fish have smaller mouths and are more difficult to catch.
The big animals of the tuna caribou are disappearing.
Meanwhile, the time has come for anything that is not too difficult as to where you live or eat.
"It's a remodeling of the tree of life," said Sarah Otto, a researcher at the University of British Columbia, whose paper was published Wednesday by the "Proceedings of the Royal" Society ", based in London.
Otto, a renowned and highly regarded theoretical biologist, says that the activities and presence of human beings have become one of the most important drivers of evolutionary change all over the planet.
"The human impacts on the world are not just local," she said. "They are changing the course of the evolutionary history for all species on the planet, and it's a remarkable concept to consider."
Earth scientists have long debated the Anthropocene – a period in Earth's history defined by geological markers of human impact. After examining dozens of research papers, Otto concluded that the biology of the planet was becoming as marked as plants and animals were reacting to human pressure.
His article is replete with examples of species of birds slowly forgetting to migrate to specially adapted mosquito breeds to underground subway tunnels.
The backyard bird feeders are causing changes in the beak shape and strength of the domestic finches. Different mammals become nocturnal to avoid human conflict. Introduced species change the basic rules for native plants and animals.
It's a mistake to think that evolution requires millennia, Otto said.
"The evolution occurs very quickly if the breeding regimes are strong, we sometimes find that plant populations change over the years."
If the changes happen too fast for the evolution to follow, there is always extinction.
It is now estimated that species loss rates are 1,000 times higher than before human domination. More than one in five plant and animal species are considered at risk.
The extinctions have always taken place. But Otto said that they were happening at such a pace and in response to similar pressures, they were reducing the ability of evolution to respond to change.
"We are losing the ability of evolution to rebound."
Forcing species into a man-made box reduces variability, leaving less room for evolution in response to future changes. And eliminating the species removes them forever.
"If we eliminate large mammals, even if humans disappear from the planet, we will not see an immediate return of ecosystems to find the right balance between small, medium and large species," Otto said.
"We are removing options, we are removing options within species by eliminating the variability, and we are also removing options at the tree of life level by removing the species."
The species that are doing well are the generalists: crows, coyotes, dandelions.
"Those who can both tolerate and thrive in man-made environments," said Otto. "The pigeons and the rats."
According to Otto, the greatest evolutionary pressure caused by humans is climate change.
"The first thing to do is to fight climate change.If we do not do it, we will lose a lot more species."
[ad_2]
Source link
