Fossilised shark teeth are known from the early Devonian, around 400 million years ago. During the following Carboniferous period, the sharks underwent a period of diversification, with many new forms evolving. Many of these became extinct during the Permian, but the remaining sharks underwent a second burst of adaptive radiation during the Jurassic, around which time the skates and rays first appeared.= = = Earl Wilbur Sutherland Jr. = = =
f ɑ s ə l aɪ z d WORD_BOUNDARY ʃ ɑ ɹ k WORD_BOUNDARY t iː θ WORD_BOUNDARY ɑ ɹ WORD_BOUNDARY n oʊ n WORD_BOUNDARY f ɹ ʌ m ð ɪ WORD_BOUNDARY ɜː l i WORD_BOUNDARY d ɛ v oʊ n iə n WORD_BOUNDARY ə ɹ ɹ aʊ n d WORD_BOUNDARY f ɔ ɹ h ʌ n d ɹ ɪ d WORD_BOUNDARY m ɪ l iə n WORD_BOUNDARY j ɪ ɹ z WORD_BOUNDARY ʌ ɡ oʊ WORD_BOUNDARY d ʊ ɹ ɹ ɪ ŋ WORD_BOUNDARY ð ə WORD_BOUNDARY f ɑ l oʊ ɪ ŋ WORD_BOUNDARY k ɑ ɹ b ə n ɪ f ə ɹ ɹ ə s WORD_BOUNDARY p iə ɹ ɪ ə d WORD_BOUNDARY ð ə WORD_BOUNDARY ʃ ɑ ɹ k s WORD_BOUNDARY ʌ n d ə ɹ w ɛ n t WORD_BOUNDARY ʌ WORD_BOUNDARY p iə ɹ ɪ ə d WORD_BOUNDARY ʌ v WORD_BOUNDARY d aɪ v ɜː s ɪ f ɪ k eɪ ʃ ə n WORD_BOUNDARY w ɪ ð WORD_BOUNDARY m ɛ n i WORD_BOUNDARY n uː WORD_BOUNDARY f ɔ ɹ m z WORD_BOUNDARY ɪ v ɑ l v ɪ ŋ WORD_BOUNDARY m ɛ n ɪ ə v WORD_BOUNDARY ð iː z WORD_BOUNDARY b ɪ k eɪ m WORD_BOUNDARY ɛ k s t ɪ ŋ k t WORD_BOUNDARY d ʊ ɹ ɹ ɪ ŋ WORD_BOUNDARY ð ə WORD_BOUNDARY p ɜː m iə n WORD_BOUNDARY b ʌ t WORD_BOUNDARY ð ə WORD_BOUNDARY ɹ ɪ m eɪ n ɪ ŋ WORD_BOUNDARY ʃ ɑ ɹ k s WORD_BOUNDARY ʌ n d ə ɹ w ɛ n t WORD_BOUNDARY ʌ WORD_BOUNDARY s ɛ k ə n d WORD_BOUNDARY b ɜː s t WORD_BOUNDARY ʌ v WORD_BOUNDARY ʌ d æ p t ɪ v WORD_BOUNDARY ɹ eɪ d ɪ eɪ ʃ ə n WORD_BOUNDARY d ʊ ɹ ɹ ɪ ŋ WORD_BOUNDARY ð ə WORD_BOUNDARY d̠ʒ j ʊ ɹ ɹ æ s ɪ k WORD_BOUNDARY ə ɹ ɹ aʊ n d WORD_BOUNDARY w ɪ t̠ʃ WORD_BOUNDARY t aɪ m WORD_BOUNDARY ð ə WORD_BOUNDARY s k eɪ t s WORD_BOUNDARY æ n d WORD_BOUNDARY ɹ eɪ z WORD_BOUNDARY f ɜː s t WORD_BOUNDARY ʌ p ɪ ɹ d WORD_BOUNDARY iː k w ə l z WORD_BOUNDARY iː k w ə l z WORD_BOUNDARY iː k w ə l z WORD_BOUNDARY ɜː l WORD_BOUNDARY w ɪ l b ɜː WORD_BOUNDARY s ʌ ð ɜː l ə n d WORD_BOUNDARY d̠ʒ eɪ ɑ ɹ WORD_BOUNDARY iː k w ə l z WORD_BOUNDARY iː k w ə l z WORD_BOUNDARY iː k w ə l z WORD_BOUNDARY