Hybrids in Nature

Feathers

The northern pintail and the mallard are two of North America’s most abundant ducks. When a male from either species mates with a female of the other, the resulting hybrid combines the elegance and sophisticated markings of the pintail with the familiar sturdiness of the mallard.

Male northern pintail Male mallard Hybrid

Feathers

On the Great Plains of North America, the Bullock’s and Baltimore orioles interbreed freely, forming an extensive hybrid zone.

Male Bullock’s oriole Male Baltimore oriole Hybrid

Petals

Iris brevicaulis and Iris fulva have different primary pollinators– bumblebees and hummingbirds, respectively– which helps limit interbreeding in the wild. Crossbreeding in the lab or for horticultural purposes, however, produces a rich variety of blossoms.

Iris fulva HybridsIris brevicaulis

Petals

Helianthus annuus Helianthus petiolaris Helianthus anomalus

Hybridization in nature between two wild sunflowers led to the natural evolution of a third species. Differences among species are evident in green bracts on the flower’s undersides.

Shells

Slime

Yellow bellied toad European firebellied toad

These hybridize over a 3,000 mile-long, 6-mile-wide area in central Europe.The offspring of these matings are often deformed; many die as embryos.

Natural HistoryNovember, 2002

About 10% of all wildplant species may haveevolved via hybridization

Paradoxically, hybridsare often very hard to find in the heart of a hybrid zone.

Resistant to being pigeonholed,hybrids have long taxed the purists.