Friday, 27 May 2022

Evolution News - Evolution is Occurring Faster Than Previously Thought

Rhesus Macaque, Macaca mulatta

Photo: Timothy Gonsalves, CC BY-SA 4.0,via Wikimedia Commons
Wild animals evolving much faster than previously thought - ANU

The precondition for Darwinian evolution is genetic difference between individuals in a population. This is the 'fuel' which drives evolution in an environment in which certain genetic variations are more advantageous than others, so the amount of this variation in any given population, is the main determinant of the rate of evolution.

In order to quantify the amount of this 'fuel of evolution', an international team led by Dr Timothée Bonnet from the Australian National University (ANU) spent three years trawling through reams of data, after which they were able to quantify how much species change occurred due to genetic changes caused by natural selection.   It turned out to be about two to four times what was previously thought and evolution can go much faster than Darwin originally thought.

The Australian Nation University news release explains:

…since Darwin, researchers have identified many examples of Darwinian evolution occurring in just a few years. A common example of fast evolution is the peppered moth, which prior to the industrial revolution in the UK was predominantly white. With pollution leaving black soot on trees and buildings, black moths had a survival advantage because it was harder for birds to spot them. Because moth colour determined survival probability and was due to genetic differences, the populations in England quickly became dominated by black moths.

We needed to know when each individual was born, who they mated with, how many offspring they had, and when they died. Each of these studies ran for an average of 30 years, providing the team with an incredible 2.6 million hours of field data. We combined this with genetic information on each animal studied to estimate the extent of genetic differences in their ability to reproduce, in each population.

The method gives us a way to measure the potential speed of current evolution in response to natural selection across all traits in a population. This is something we have not been able to do with previous methods, so being able to see so much potential change came as a surprise to the team.

Whether species are adapting faster than before, we don't know, because we don't have a baseline. We just know that the recent potential, the amount of 'fuel', has been higher than expected, but not necessarily higher than before.

This research has shown us that evolution cannot be discounted as a process which allows species to persist in response to environmental change, but what we can say is that evolution is a much more significant driver than we previously thought in the adaptability of populations to current environmental changes.

Dr Timothée Bonnet, lead author
Research School of Biology
Australian National University
Canberra, ACT, Australia.
The study is the first time the speed of evolution has been systematically evaluated on a large scale, rather than on an ad hoc basis. The team of 40 researchers from 27 scientific institutions used studies of 19 populations of wild animals from around the world. These included superb fairy-wrens in Australia, spotted hyenas in Tanzania, song sparrows in Canada and red deer in Scotland.

[…]

After three years of trawling through reams of data, Dr Bonnet and the team were able to quantify how much species change occurred due to genetic changes caused by natural selection.

[…]

This has been a remarkable team effort that was feasible because researchers from around the world were happy to share their data in a large collaboration.

It also shows the value of long-term studies with detailed monitoring of animal life histories for helping us understand the process of evolution in the wild.

Professor Loeske E. B. Kruuk, co-author
Research School of Biology
Australian National University
Canberra, ACT, Australia.
However, the researchers warn it's too early to tell whether the actual rate of evolution is getting quicker over time.

According to the researchers, their findings also have implications for predictions of species' adaptability to environmental change.

Dr Bonnet said that with climate change predicted to increase at an increasing rate, there is no guarantee that these populations will be able to keep up.


The team have published their research, in the journal Science:
Rapid change

Human impacts are leading to exceedingly rapid alteration of our world, from land conversion and habitat loss to climate change. Some have proposed that rapid adaptation could help some species persist in the face of these changes, but questions remain about whether adaptation could occur rapidly enough to make a difference. Bonnet et al. looked at additive genetic variance, which determines the contribution of selection to genetic change that increases fitness, in long-term data from 19 species and found it to be higher than expected—often substantially higher (see the Perspective by Walsh). These results suggest that many species may have some capacity to adapt to our changing world. —SNV

Abstract

The rate of adaptive evolution, the contribution of selection to genetic changes that increase mean fitness, is determined by the additive genetic variance in individual relative fitness. To date, there are few robust estimates of this parameter for natural populations, and it is therefore unclear whether adaptive evolution can play a meaningful role in short-term population dynamics. We developed and applied quantitative genetic methods to long-term datasets from 19 wild bird and mammal populations and found that, while estimates vary between populations, additive genetic variance in relative fitness is often substantial and, on average, twice that of previous estimates. We show that these rates of contemporary adaptive evolution can affect population dynamics and hence that natural selection has the potential to partly mitigate effects of current environmental change.

I hope it's not too big a shock to creationists dupes to discover that, not only have they been fooled into believing the Theory of Evolution is a theory in crisis with serious biologists increasingly rejecting it as the best available explanation for biodiversity, but that it is the foundational principle behind science such as this, and the evidence is that it can go much faster than Charles Darwin believed but 2-4 times faster than most modern biologists thought.

But, as usual, I expect creationists to ignore the science and just keep chanting the mindless mantras they've been conditioned to chant, without the slightest understanding of the scientific evidence or the slightest interest in the truth.

Thank you for sharing!









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