Image: Science/John Kress, Smithsonian
A diagram showing the complementary morphology of female (A) and male (B) purple-throated carib hummingbirds, and the flowers they pollinate, H. bihai (C) and H. caribaea (D). This example of bird sex-to-flower species co-evolution is rarely observed in nature, but clearly demonstrates a highly specialized inter-species relationship that developed over the course of millions of years.
