What recent experimental evidence suggests that all animal appendages may be homologous?

The discovery of the "distal-less," or Dll, gene in many different phyla
New tests on fossils for common ancestral appendage types across phyla
Recent changes in model analyses of the morphological features of animal phyla
The discovery of a regulatory protein for muscles in many different phyla

The discovery of the "distal-less," or Dll, gene in many different phyla.

Explanation: Appendages of animals are any external attachment or extension of one or two body parts of an organism in order for it to be able to effectively perform its responsibilities.

The morphological and functional changes or evolution of appendages is responsible for the adaptive radiation of tetrapods, arthropods and winged insects. Recent studies tends to show that all animal appendages may be homologous through the discovery of the "distal-less," or Dll, gene in many different phyla.

clumped distribution, because you'de have all of the population gathered in a relatively small are.

it's the most common because it provides protection and a mate for reproduction

example: humans, seeweed, cattles, etc.