Placoderms evolved from jawless fish, an agnathan group called ostracoderms. However, this evolution is a grey area and it is not known how or why this event took place. In Willian Patten‰s 1932 paper entitled ‹Foundation of the FaceŠ in which he discusses vertebrate origin, Dr Patten eloquently expresses this puzzlement.
"all evolutionary phenomena are fundamentally inexplicable... We see all these mysterious rabbits come out of a magic hat. That is all. The sequence, and the source, are the only clue to understanding... The amazing performance proceeds, openly and regularly, yet no one can see how the trick is done. But we suspect there is some sort of collusion between the Magic Hat and all these goddamn rabbits." |
ostracoderms evolved into a variety of shapes and forms