Pseudopods are by far the most successful clade of terrestrial bipods aboard the Rhynia, far exceeding both the haruspicamorphs and the pandromaeopods in terms of diversity. A major contributing factor to this is their additional limbs, derived from claspers. Of the pseudopods, the earliest known fossil species was an inconspicuous insectivore found on one of the myriad northern bridge islands. Given the name Latacephalus podifora for its broad head, it has given plenty of insight on the evolution of its group.
The preserved skin membrane of an individual's hindlimb hints at its relationship to a group of early bipods, the eusthenopods. Based on this observation, the following theory has been made: At some point in the late Carboniferous, some eusthenopods likely rafted over to the northern islands. Faced with Foster's rule, their size shrank drastically, reaching sizes of mainland thelocauds. Soon, a group of these rafters adapted their claspers as support structures, which allowed them to become better burrowers. The males of this species still retain their flagging organs, evident from fossil records, and possibly performed the same sort of mating dance exhibited by extant lost micro-continent eusthenopods. At one point, they possibly rafted back to the various micro-continents, and from there diversified into the myriad forms we still see today.
Comments
Post a Comment