Robin's nest with a brown-headed cowbird egg
© Edward Kinsman/Science Photo Librar
Freeloaders of the avian world
Ever felt like some folks are just born jerks? Birds can relate. Take for example the uninvited speckly-white visitor to this robin's nest: That smaller egg belongs to a baby cowbird whose mother sneakily laid it among the blue robin eggs when no one was looking. Once the baby birds all hatch, the cowbird will grow much faster and larger than its robin 'siblings,' soon becoming an only chick by muscling them right out of the nest. And if mama robin ejects the cowbird egg before it hatches, the cowbird mom may take notice and chuck the remaining robin eggs from the nest out of spite.
Don't direct all your righteous ire at the cowbird, though—plenty of critters get by on underhanded tactics (even if you don't count humans!).
Barley field in East Lothian, Scotland
Tiger camouflaged amongst tall grass, Assam, India
Rows of different lavender plants in a field in the Cowichan Valley in British Columbia
'Field of Light' by artist Bruce Munro at Uluru, Australia
The Vermilion Lakes in Banff National Park, Alberta
Boats float by rice fields on the Ngo Dong River in Ninh Binh province, Vietnam
Moose crossing a pond below Mount Moran, Grand Teton National Park, Wyoming
Tawny frogmouth chick, Australia
