棕色喉三趾树懒(Brown-throated three-toed sloth)

哥斯达黎加郁郁葱葱的森林是两种树懒的栖息地：霍夫曼的二趾树懒和今天主页上的明星——棕色喉三趾树懒。尽管三趾树懒比许多树栖哺乳动物都大，但它们已经通过减少肌肉量和体型来适应在树梢上茁壮成长。它们的大胃有四个腔室，当饱腹时，这些腔室可以占它们体重的30%。这些毛茸茸的动物久坐不动，以至于它们的皮毛上长满了藻类。这种共生关系为它们提供了绿色色调，在雨林树冠内提供了有效的伪装。2021年，这些行动缓慢的生物在哥斯达黎加被宣布为国家象征。时任总统卡洛斯·阿尔瓦拉多于2021年将该倡议签署为法律，以强调树懒在国家生态系统中的重要性。
原文：
Costa Rica's lush forests are habitats for two sloth species: Hoffmann's two-toed sloth and the star of today's homepage, the brown-throated three-toed sloth. Despite being larger than many tree-dwelling mammals, three-toed sloths have adapted by reducing their muscle mass and size to thrive on treetops. Their large stomachs have four chambers, which can make up to 30% of their body weight when full. These shaggy critters are so sedentary that algae grow on their coats. This symbiotic relationship provides them with a greenish hue, offering effective camouflage within the rainforest canopy. In 2021, these slow-moving creatures were declared national symbols in Costa Rica. Then-President Carlos Alvarado signed the initiative into law in 2021 to emphasize the sloths' importance in the country's ecosystem.
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