mammals are most closely related t :
A, amphibians
B. birds
C. arthropods
tks.
birds
thank you cam for your help.
To determine which group of animals mammals are most closely related to, we need to look at their evolutionary relationships. One way to do this is by examining their anatomical and genetic similarities.
Comparative anatomy studies have shown that mammals share several characteristics with birds, such as having a four-chambered heart, a high metabolic rate, and the presence of feathers (in some cases). However, these shared features are considered to be the result of convergent evolution rather than a close evolutionary relationship.
On the other hand, comparative genetics studies, particularly DNA sequencing, have provided strong evidence that mammals are most closely related to reptiles and birds. This grouping, known as the amniotes, includes all animals that lay eggs with an amniotic membrane, such as birds, reptiles (including dinosaurs), and mammals.
Amphibians, despite being tetrapods like mammals, are actually more distantly related to them. During their evolutionary history, amphibians branched off earlier than reptiles, birds, and mammals.
Arthropods, which include insects, spiders, and crustaceans, are even more distantly related to mammals. They belong to a completely different phylum (Arthropoda) and have vastly different body plans and genetic characteristics compared to mammals.
Therefore, based on our understanding of evolutionary relationships from both comparative anatomy and genetics, we can conclude that mammals are most closely related to birds among the options you provided.