Evolution Gives Me Butterflies
What is that queasy feeling in my stomach? Is it because evolution gives me butterflies?
A recent article in Phys.org claims that evolution has been using the same genetic cheat sheet for over 120 million years, suggesting that life on earth may be more predictable than first imagined. They studied several distantly related South American rainforest butterfly and moth species that sport similar wing color patterns that warn away predators.
The genetic changes in the different butterfly species did not happen in the genes themselves, but in similar "switches" that turn the genes on or off. The moth species surprisingly used an inversion mechanism—a large chunk of DNA flipped backwards-a near identical genetic trick used by one of the butterflies.
Professor Kanchon Dasmahapatra, from the University of York's Department of Biology, said, "Convergent evolution, where many unrelated species independently evolve the same trait, is common across the tree of life. But we rarely have the opportunity to investigate the genetic basis of this phenomenon.
When scientists cannot explain the origin of something, or why it has a purpose, often they make up a name for it like "convergent evolution".
Professor Joana Meier, from the Wellcome Sanger Institute, said, "These distantly related butterflies and the moth are all toxic and distasteful to birds trying to eat them. They look very much alike because if birds have already learned that a specific color pattern means "do not eat, we are toxic," it is beneficial for other species to display the same warning colors.
"Here, we show that these warning colors are particularly ideal as it seems quite easy to evolve these same color patterns due to the highly conserved genetic basis over 120 million years."
Knowing that nature follows a particular route and is not as "random" as once thought, helps scientists predict how other species might adapt to their environments, or climate change.
Creationists have a more reasonable explanation. The reason distantly related butterflies share similar characteristics is because they have the same designer, just like a computer programmer writing different applications but reusing the same code.
A real dilemma for evolutionists is the life cycle of the butterfly. The life span of a butterfly is so short that mutations don’t have a chance to appear and become fixed in the genome. Explaining the metamorphosis of the butterfly results in a lot of logical machinations.
While the evolutionary advantages of complete metamorphosis are clear, the details of how this complex process first evolved remain murky.
"There are two main schools," Xavier Bellés Ros, an ad honorem researcher at the Spanish National Research Council, told Live Science in an email.
One idea, supported by Bellés Ros, proposes that complete metamorphosis evolved as the nymph stage split into the larval and pupal phases. The opposing camp, supported by researchers including Truman, argues that the larval stage originated from an embryonic phase known as the pronymph, the brief phase when an insect first begins to emerge from its egg.