Big Bird

Darwin outdated: animal species evolve in two generations

Start
In barely two generations, a new species of bird has appeared on the Galapagos island. This is an incredible phenomenon when you consider that the pace of evolution usually extends over many generations. Darwin would not have believed his eyes! This speed is to be compared to the pressures that humans put on the evolution of hundreds of species, forcing them to change willy-nilly. What we now know is that all this can go fast, very fast.
 
C’t is on an isolated island in the Galapagos Archipelago that researchers have observed a new species of bird, produced in just two generations. The animal was named Big Bird by the scientists behind the study, published in the journal Science.  
 
This study by researchers from Princeton University and Uppsala University is based on research on Darwin's finches, native birds of the Galapagos Islands. This mythical archipelago, where Darwin forged his theory of evolution, is a unique natural bubble. Scientists can observe evolution in its pure state, driven only by nature.
 
Rosemary and Peter Grant, two Princeton scientists, wanted to take a closer look at the mechanisms of this evolution. So they settled for four decades on the small island of Daphne Major. « The novelty of this study is that we can track the emergence of new species in the wild... " Katie Bays, co-founder of the consulting firm Sandhill Strategy, said B. Rosemary Grant, Professor Emeritus of Ecology and Evolutionary Biology and Senior Research Biologist. « Thanks to our work on Daphne Major, we were able to observe the pairing of two birds of different species and follow what happened to see how speciation occurred. "
 
The famous biologist Peter Grant on Daphne Major Island in the Galapagos.
 
It all started in 1981, when a student of the Grant's noticed a male bird with a slightly different song, with a body and beak much larger than the three native species on Daphne Major. « We did not see him enter by the sea, but we noticed him shortly after his arrival. It was so different from the other birds that we knew it hadn't hatched an egg on Daphne Major. "says Peter Grant, Professor Emeritus of Zoology, Ecology and Evolutionary Biology.
 
Blood and DNA samples allowed researchers to discover that the strange new bird was in fact a large cactus finch of the species Geospiza conirostris native of the island of Española, located more than 100 km from Daphne Major. The "Big Bird" mated with a medium-sized native finch, Geospiz fortisand created an entirely new line of Big Birds. This happened because the cactus finch could not fly the long distance to its home island, and was therefore forced to choose a mate from one of the bird species living on Daphne instead of a fellow bird of its own species.
 
The researchers involved in this study noted that such a remarkable and rapid evolution was made possible by reproductive isolation, which is a critical step in the creation of a new species from the crossing of two distinct species. Until now, it was generally accepted that the evolution of a new species takes a long time. However, due to the unique circumstances and environment offered by this isolated archipelago, "Big Bird" has proven to researchers that the evolution of a new species is possible in only two generations.
 
As pollution and climate change rage, scientists are discovering that evolution can happen when and where we least expect it. Increasingly, we are finding that, with the exception of natural anomalies such as "Big Bird", human action can significantly influence evolution. From what we put into the atmosphere to how we expand our urban environments, animals around the world are adapting and evolving.
 

Unnatural selection

 
Indeed, recent research shows that many of our activities exert significant unintended selection on organizations. Such a unnatural selection « as the BBC Professor Adam Hart of the University of Gloucestershire, causes these populations to evolve as the inevitable logic of Darwinian selection comes into play.
Perhaps the best and most important example of an unintended evolution resulting from our activity is antibiotic resistance. Antibiotics place enormous selection pressure on bacteria and there is a huge benefit to anyone who can resist. Similarly, pesticides are selected for pesticide resistance.
 
Some well-known examples of selection and unnatural evolution come from commercial fisheries. It is the larger fish that are usually targeted and those that remain are therefore smaller. But this effect does not only reflect a demographic change.
Dr. Eric Palkovacs of the University of California Santa Cruz explained : " We've removed the big fish, and that has a direct effect on the size structure of a population. Subsequent populations will feel that impact because these small fish bring more genes to the population. "In other words, "smallness" genes thrive while "greatness" genes are selectively eliminated by fishing.
 
In the same way, urbanization leads de facto to a selection of species capable of tolerating the environments we create. Globally, we are causing climate change that imposes further selection pressures that we do not yet fully understand.
It seems that practically everything we do can have an unintended evolutionary consequence.
What we now know is that the phenomenon is unfolding at an unprecedented rate.
 
Sources: Science, Futurism, Phys.org, BBC
Header image: Big Bird © PR Grant
 

0 Comments
Inline Feedbacks
View all comments
biodiversity
Previous article

Artificialization of land: in order to tax it, it must be well defined.

bird turbines
Next article

Biodiversity and renewable energies: dangerous connections?

Latest articles from Biodiversity

JOIN

THE CIRCLE OF THOSE WHO WANT TO UNDERSTAND OUR TIME OF TRANSITION, LOOK AT THE WORLD WITH OPEN EYES AND ACT.
logo-UP-menu150

Already registered? I'm connecting

In order to contribute to the information effort on the current coronavirus crisis, UP' proposes to its readers a free entry to the latest published articles related to this theme.

→ Register for free to continue reading.

JOIN

THE CIRCLE OF THOSE WHO WANT TO UNDERSTAND OUR TIME OF TRANSITION, LOOK AT THE WORLD WITH OPEN EYES AND ACT

You have received 3 free articles to discover UP'.

Enjoy unlimited access to our content!

From $1.99 per week only.
0 Shares
Share
Tweet
Share
WhatsApp
Email
Print