Wild Wonders of Europe / Giesbers / European yellow rattle (Rhinanthus alectorolophus) flowering in alpine meadow, Liechtenstein, June 2009

Michael D. Kern / Mojave Sidewinder rattlesnake with tongue flickering and rattle raised {Crotalus cerastes cerastes} captive from California, USA

Juergen Freund / Scientists on the Undersea Explorer research vessel testing a coconut rattle to attract sharks. Queensland, Australia. John Rumney.

John Cancalosi / Western diamondback rattlesnake close up {Crotalus atrox} rattle visible, Texas,

Rolf Nussbaumer / Greater yellow rattle flower {Rhinanthus alectorolophus} Switzerland.

ZSSD / Colorado Desert Sidewinder (Crotalus cerastes laterorepens) on sand, venomous species native to deserts of California and Mexico

Michael & Patricia Fogden / Black-tailed Rattlesnake (Crotalus molossus) portrait, Chiricahua Mountains, Arizona

Jim Brandenburg / Western Rattlesnake (Crotalus viridis) in defensive posture, South Dakota

Larry Minden / Red Rattlesnake (Crotalus ruber) coiled on ground, Baja California, Mexico

Larry Minden / Red Rattlesnake (Crotalus ruber) with tongue extended, Baja California, Mexico

Jim Brandenburg / Western Rattlesnake (Crotalus viridis) in defensive posture, South Dakota

Daniel Heuclin / Panamint rattlesnake (Crotalus stephensi) with tongue out and rattle raised, on rock. Amargosa Desert, Nye County, Nevada. May.