"Catching Lizards in the Act of Adapting"
The article I chose was one in the Science magazine, dealing with adaptation
in lizards. Jonathan Losos of Washington University in St. Louis
and colleagues conducted a study involving the Anolis sagrei lizards.
What they did was take a population of the Anolis sagrei lizards to Staniel
Cay in the Bahamas to conduct the study that reptiles would indeed become
instinct. They hypothesized that putting a species of animals in
an environment they have never been in would be hard for them to survive.
They later did find out that their hypothesis was incorrect. What
they learned is that their "extinction study turned into a demonstration
of evolution in action." Adaptation is sometimes used to refer to
a process of change in evolution. The Anolis learned that in order
to survive and inhabit the new environment that some body changes had to
be made. These changes do indeed bring the previous study that had
been done about the finches in the Galapagos Islands. The study showed
that in order to survive in different an environment, different changes
occurred, in which brings new species to the environments. In the
research with the lizards, researchers say the hind legs of the lizard
grow shorter, in which they were adapting to the surroundings of bushy
vegetation. Some of these changes were rapid, but in some cases,
the adaptation took time. In responding to previous studies, Losos
and his team came to conclusion that in some cases of adaptation might
not be genetic, but instead environmental. And if indeed it is genetic,
then their "study is strong evidence that isolated population diverge by
natural selection, not genetic drift, as some theorist have argued."
After twenty years, the lizards adapted by growing shorter limbs.
Evidence does not yet support either natural selection or simple developmental
adaptation. The research does continue. Losos is taking his
natural radiation experiment one step further by introducing two closely
related species of lizards on lizard-free islands. What he wants
to see is if competition will occur between the two of them and what adaptations
will occur in the process of survival.
This article was very interesting. Not only does it help explain
the process of evolution, but also gave me an understanding about how some
species of animals adapt to certain surroundings in order to survive.
I would definitely recommend this article to my fellow classmates.
I was also fortunate to find an article on the type of animal I am doing
for my WhoZoo project.
Source:
Morell, Virginia. "Catching Lizards in the Act of Adapting". Science.
2 May 1997, vol 276, p.682(2).