Chinese scientists have found an interesting sample–a cretaceous symmetrodont therian with some monotreme like postcranial features–in the Liaoning fossil beds which they have named Akidolestes cifellii.
Within eutriconodontans, lumbar ribs are present in gobiconodontids but not in the related Jeholodens. Within spalacotheroids, these are present in Akidolestes but absent in zhangheotheriids. Outside the crown mammals, lumbar ribs are absent in morganucodontans but variably present in many advanced cynodonts. It is possible that this rampant homoplasy of the lumbarosacral vertebral ribs is patterned by developmental genes that are deeply conserved in widely separated mammalian taxa that lacked a recent common history. However, homoplastic development of the lumbar ribs is not mutually exclusive of the interpretation that these ribs and related features also have convergent function to extant monotremes.
There are several ways to interpret the data:
1. Conservation of Developmental Genes – These structures were deeply conserved from a time before these groups split apart.
2. Convergent Evolution – The environment funneled their body features to become similar. On a side note this has supposedly happened many times with the eye.
Obviously the scientists–being Darwinists–decided to favor those two interpretations as the only valid interpretation. Not that they attempted to refute other interpretations…they just didn’t consider them.
3. Latent Library or Prescribed Evolution
4. Designer Reuse – One of the positive cases for Intelligent Design is the observation of the ways designers act when designing. Intelligent agents often Ã¢â‚¬Ëœre-useÃ¢â‚¬â„¢ functional components that work over and over in different systems.
I can think of other interpretations but that’s enough for one discussion.
On a side note, the Platypus was originally considered by taxonomists to be a hoax considering its diverse number of features.
Way, way off topic…I have the theme song for Trigun stuck in my head. Hey, this animal is weird enough that I have the right to be weird in writing this post. 😉