发布网友 发布时间:2022-04-30 16:27
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热心网友 时间:2022-06-27 11:27
A fish is a water-dwelling vertebrate with gills that doesn't change form, as amphibians do, ring its life. Most are cold-blooded, though some (such as some species of tuna and shark) are warm-blooded. There are over 29,000 species of fish, making them the most diverse group of vertebrates. Taxonomically, fish are a paraphyletic group whose exact relationships are much debated; a common division is into the jawless fish (class Agnatha, 75 species including lampreys and hagfish), the cartilaginous fish (class Chondrichthyes, 800 species including sharks and rays), with the remainder classed as bony fish (class Osteichthyes).热心网友 时间:2022-06-27 11:27
乌鸡白凤的英语解释