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loco plant

any of certain plants belonging to the genera Astragalus or Oxytropis that grow wild in western North America, particularly in the Rocky Mountains, and that if ingested damage nerve tissue. The substances responsible include miserotoxin, swainsonine, and selenium. Symptoms of poisoning include muscular trembling or incoordination, staggering gait, and impairment of depth and other sensory perception (loco is the Spanish word for “crazy”). In sufficient doses, these toxins produce irreversible changes in the central nervous system, including brain lesions and eventual paralysis, and may cause coma or death. Also called loco weed.

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Psychology term of the day

February 16th 2025

sun compass

sun compass

the use of the sun as a directional stimulus in orientation and navigation. Because the sun appears to move across the sky during the day and has different trajectories in different seasons, a sun compass must be coupled with some form of time estimation. To head south at 9 a.m., one needs to keep the sun on the left, but at 3 p.m., one needs to keep the sun on the right. Studies of several species, ranging from bees to fish and birds, have demonstrated a time-compensated sun compass. For nocturnal species, there is evidence of a star compass.