EVOLUTION WORKS IN FAST, LOCALIZED, MYSTERIOUS WAYS
- popular story I wrote about my Ph.D. research, published by Slate (link here)
When I first stepped foot on California’s picturesque Santa Cruz Island, I was in awe. The foxes were tame, the jays were supersized, and the wildflowers grew like trees. I knew that islands were renowned for harboring unusual species. But I didn’t know that there was more to the biodiversity of this small island than met the eye—let alone that I would play a role in discovering it.
Islands have played a central role in the quest to uncover how evolution operates. A comparison of species on the Galápagos Islands and neighboring South America seeded Charles Darwin’s insight that similar species share a common ancestor. And later work on Darwin’s finches revealed that evolution isn’t just a slow, steady process spread out over millennia; it can occur rapidly and alter the characteristics of a population from one year to the next.
Islands are the test tubes of nature. Depending on the island (and the species) in question, many of them are closed off, rarely playing host to immigrants. This isolation allows species to adapt to the characteristics of their particular island home without the potentially meddlesome influence of “foreign” genes brought in by individuals from faraway lands. That’s why islands are hotbeds for the generation of new species.
But, as I found out on Santa Cruz Island, evolution doesn’t stop there. The process can also generate biodiversity within islands, not just as you go from one island to another. This came to light during my Ph.D. research spent studying a brilliant blue bird called the island scrub-jay, found only on Santa Cruz.
Read the rest of the story here.