Virtually everything about them, from their morphology to their embryological development to their behaviour to their genomes.
There has been no evidence of such an ancestor.
Gene based phylogenetic studies indicate that annelids and mollusks share a recent common ancestor
yes they do in facts share a common ancestor.
Mollusks and segmented worms have a one-way digestive system, a separate mouth and anus, and their larvae are very similar. This is the best evidence that they have a common ancestor.
Yes, plants and animals share a common ancestor.
If species are said to have a common ancestor, it means they are believed to have descended from a single, shared ancestor species in the past. This indicates that despite differences observed in the species today, they share a genetic and evolutionary heritage that links them back to a common origin.
An ancestor.
The common ancestor that two or more descendants share is a shared ancestor from whom they both or all descend.
The DNA genetic code provides the best evidence of the common ancestry of life. Science has shown that there are many similarities between DNA sequences.
The branch point in a cladogram represents a specific ancestor that is separated into two or more species. For example a leopard and a house cat share a common ancestor. A similar example is that a wolf shares a common ancestor with the leopard's and house cat's ancestor but the wolf's ancestor lived longer than the leopard's and house cat's ancestor. Scientists use something called cladistics to determine the one common ancestor that multiple species have in common.
Yes these two share common ancestors.
Only if you share a common ancestor. This is seldom the case. Technically, there is no relationship.