Human perturbation has a major impact on the evolution of other organisms: Study | The Weather Channel – Articles from The Weather Channel

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Is evolution a rapid process that happens “all around us all the time”? Evolutionists point to an example of the large Alberta sheep’s horn size which has decreased due to trophy hunting.

They say that wild populations must continually adapt to environmental changes or face extinction.

For more than 50 years, scientists have described cases of “rapid evolution” in certain populations where their traits (phenotypes) change in response to changing stresses.

For example, Spanish clover has developed a tolerance to copper from the tailings of the mines in which it grows.

But until now it has not been possible to reach any comprehensive conclusions about how various factors (such as harvesting, climate change, invasive species or pollution) have shaped this rapid (now called “contemporary”) development.

Building on previous work, a team led by McGill University has created a massive new data set of nearly 7,000 examples of trait change in different populations around the world, from house sparrows and gray wolves to freshwater snails and Canadian gold bars.

The data set is 80 percent larger than any in the past and documents trait changes that are a combination of evolution and immediate (plastic) responses to the environment.

Human disorders affect evolution.

Andrew Hendry, professor of biology at McGill’s Redpath Museum and co-author of the paper, “The Pace of Modern Life, Revisited,” recently published in Molecular ecology.

The researchers were particularly interested in how different types of human disorders affect changes in traits. “We found a small but real difference in rates of change between disturbed human and natural populations,” explains Kiyoko Gotanda, co-lead author, and assistant professor of biological sciences at Brock University where the data is located.

“Moreover, the highest rates of change are almost always those associated with intense human disruption,” Hendry adds.

The researchers say pollution has a significant impact on evolution.

Expanded data set analyzes also confirm that harvesting by humans leads to greater rates of change than non-human disturbances, and that introduced populations have increased rates of change.

Interestingly, the researchers found that contamination was responsible for the fastest rate of change in the phenotype — with the zinc tolerance of hair grafts increasing 80 percent over a 26-year period, for example.

They also suggest that it is now difficult to judge what is a “natural habitat” because climate change will probably affect most of the population.

“The next important question is how important this contemporary change is to populations, societies, and ecosystems, as well as to nature’s contribution to people,” adds first author Sarah Sanderson, a PhD student in biology at McGill University.

“We know, for example, that salmon has gotten smaller over the past century. This decrease in body size for such an important fish has massive effects – birds, bears and fish now have less food to eat, and the natives have to catch more fish per meal. The return is lower for commercial fishermen.

“Similar effects must certainly attend to many other changes in traits that have been observed in countless organisms around the world,” Hendry adds.

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The above article was posted from a wired source with minimal modifications to the title and text.

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