June 2017 - What do pygmy mammoths, island foxes, and Santa Cruz Island gopher snakes have in common? Sure, they’re all vertebrates found at one time or another in Channel Islands National Park, but there’s something else. All are dwarf species with larger mainland counterparts (Columbian mammoths, gray foxes, and Pacific gopher snakes).
It is not unusual to find dwarf species on islands. Biologists have long noted high frequencies of dwarfism, and also gigantism, on islands around the world. Fewer predators is one possible explanation for gigantism, while dwarfism is thought to evolve as a result of more competition or less food availability. An example of a living giant in Channel Islands National Park is the island scrub jay, 1/3 larger than mainland scrub jays.