Sign up for CNN’s Wonder Theory science newsletter. Explore the universe with news on fascinating discoveries, scientific advancements and more. In a Costa Rican ...

The creature is small, somewhat furtive and green. Sometimes it’s brown. It has a voracious appetite for insects and spiders but is completely harmless to people. It clings to walls and screens and ...

A green anole lizard fans its dewlap while prowling along a fence on South Forest Beach on Thursday. The red flap of skin is used by males of the species to signify possession of territory or to ...