Charles Darwin, also known as the father of evolution, explored various aspects of the Galapagos Islands during the 1830s. However, what are known as "Darwins finches" arguably became the most memorable and scientifically significant aspect. The slight differences within the birds Darwin found during this expedition all only had slight variants, which turned out to be adaptions that occurred as a result of speciation and natural selection.
The image above shows how from a common ancestor, several species of birds were created.
The first stage of speciation is the isolation of species populations; historically, this is often seen as a result of natural causes, such as river formations creating isolation.
The first stage of speciation is the isolation of species populations; historically, this is often seen as a result of natural causes, such as river formations creating isolation.
Today however, we're experiencing speciation in ways we haven't before as a result of urban influence. Rather than a river forming, buildings are built across natural spaces. Pigeons, a bird seen daily by many, are showing unexpected reactions to urbanization. Elizabeth Carlen, a biologist at Fordham University, discovered that from Virginia to Southern Connecticut Pigeons were interbreeding. However, beyond that, pigeons north of Connecticut seemed to have their own agenda. Even Carlen was shocked by these results, saying "My original hypothesis was that each city was going to be a separate population"
Scientists hypothesis that this gap in interbreeding that is marked by Connecticut is a result of a break in urban sprawl; from Boston to Connecticut, there's a large greenway intercepting the path of potential travelers from the pigeon population. Often relying on food from passerby and garbages, this greenway may discourage pigeons from beginning the journey due to the convenience they're offered in urban areas.
Jonathon Losos, an evolutionary biologist at Washington University in St. Louis, may have summed up what everybody is thinking by saying, “I mean, who pays attention to pigeons? To find out that there’s an interesting biological phenomenon about how they might be evolving is quite fascinating."
While future intents to further research the matter exist, despite being right in front of the public, pigeons often go unnoticed. As a result, right now, very little is known about the specifics.
NYT article covering subject:
Elizabeth Carlen & John Munshi South's initial study:
Learn more about Charles Darwin's finches:
Learn more about speciation:
Learn more about urbanization and wildlife:
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