Question

your hypothesis is that marsupials first originated in gondwana (the southern supercontinent that included what would later become south america), and then lineages diverged due to vicariance and dispersal as continents became separated, or joined, over time. true or false: if your hypothesis is true, then north american marsupials would represent the most recent lineage of marsupials on a phylogenetic tree.

Answer 1

It is false that North American marsupials would represent the most recent lineage on a phylogenetic tree, considering the hypothesis that marsupials originated in Gondwana and later diversified. The North American species are likely not the most recent due to continental rearrangements and subsequent isolation and diversification, particularly in Australia.

Step-by-step explanation:

The hypothesis that marsupials first originated in the supercontinent Gondwana and later diverged due to vicariance and dispersal suggests that the geographic isolation played a significant role in their evolutionary history. According to this hypothesis, it is false to say that North American marsupials would represent the most recent lineage of marsupials on a phylogenetic tree. Marsupial diversification is deeply tied to continental drift and the isolation of Australia, leading to a great variety of endemic species. As marsupials originated before the breakup of Gondwana and dispersed across various continents, it is likely that South American marsupials are more closely related to Australian marsupials than North American species, given that North America was connected to Eurasia rather than Gondwana.