BIO153H5 Lecture Notes - Lecture 17: Blacktip Reef Shark, Spotted Ratfish, Southern Stingray
Document Summary
30 millions years later, 420 mya, have 3 distinct lineages. Actinistia: this tree on slide 4 = phylogram. Jaws evolved: in the chondrichthyes, the cartilaginous skeleton is , an ancestral characteristic or a derived characteristic, derived character. 3: need to find out if skeleton had a skeleton or not. It was assumed that ancestral characteristic: biggest fish alive today, whale shark. Fish who you can seen their brain - wow science. Crucial for our existence: osteichthyans mean = fish that are bony. Oste = bone ichthyes = fish: a perch"s head is almost all moveable parts. Feed by sucking prey into mouth by a fraction of a second: moray eels have moveable second jaw. Tuna and sharks: tuna and sharks show regional heterothermy. Some tune and sharks show regional heterothermy, this means that . Different muscles work at different temperatures work at ultimately.
