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Dragonfly mating wheels and guarding behavior

When compared to monkeys and apes and humans, dragonflies are ancient. The earliest common ancestor to primates lived 85 million years ago, but fossils of dragonflies were deposited 325 million years ago. Ancient dragonflies called “griffinflies” were enormous — their bodies were 17 inches long and their wingspans were 28 inches.


U.S. forests transformed by series of invading species

As our world becomes smaller and people become more mobile and commerce becomes more international, species get moved from place to place at an ever-increasing rate.


Cliff swallows mine mud to make nests

Late in the day on the south side of Poncha Pass, I witnessed a spectacle of frantic avian industry: Cliff swallows were mining mud from a puddle.

They would approach from the north, wheel around and swoop down to approach from the south. They dropped into a mud flat beside the puddle, where the mud was just right — malleable, but neither soupy nor crumbly. Their feet sank into the mud, and they scooped mud into their beaks while fluttering their wings continuously. After a few seconds of working the mud in their beaks, perhaps forming it into pellets, they flew off.


Spruce adelgids trick trees into making galls

Tiny tangles of white fluff appeared on blue spruces in the last several weeks.


Chokecherries invite pollinators and frugivores, but poison herbivores

Chokecherries are blossoming, filling the air with a pleasant fragrance and attracting pollinators.
Chokecherry, Prunus virginiana, is a small tree or shrub with an immense range, from the Atlantic to the Pacific in Canada and in most of the 48 contiguous states with the exception of those in the southeast.