Seemingly, laser eyes would give cats an evolutionary advantage as predators. However, there are no likely mutations in their genetic material that would allow cats to project lasers from their eyes. Without such mutations, natural selection cannot favor the evolution of this trait.

Natural selection requires variation upon which to act. Therefore, evolution isn’t only about the survival of the fittest, it also requires the arrival of the fittest through a mutation that causes a beneficial trait.

Meet Trisha Wittkopp

Trisha Wittkopp, PhD, is Arthur F. Thurnau Professor, Sally L. Allen Collegiate Professor of Ecology and Evolutionary Biology and Molecular, Cellular, and Developmental Biology at the University of Michigan.

 

Mutations

Wittkopp’s research focuses on the rise of genetic changes through mutations over evolutionary time. Mutations are the key to biodiversity and are responsible for the diverse beauty in the natural world.

 

Why Don’t Pigs Fly?

The developmental process within each species shapes what’s possible in mutations. For example, humans are usually symmetrical, so our left and right hands are mirrored.

This concept of constraint means that although we can imagine flying pigs, there is no genetic change that can cause that trait in pigs, so we may never see the day pigs fly!

 

Working with Fruit Flies

The Wittkopp Lab studies the genetic basis of differences that can be seen in cell types, between individuals of the same species, or between species. Working with different fruit fly Drosophila species, Wittkopp and her team look at variable traits such as pigmentation to study the role of gene expression.

 

One in a Million

To study the effects of new mutations and how they introduce variation, Wittkopp uses baker’s yeast, or Saccharomyces cerevisiae. Fruit flies have a generation time of two weeks, but in one day, yeast can reproduce in the millions.

That means that in a much shorter time, researchers can track the inheritance traits over time, and search for rare mutations in individual yeast cells.

 

 

 

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