If a blastopore forms the anus during early gastrulation, what are these animals called?

Animals in which the blastopore forms the anus during early gastrulation are classified as deuterostomes. This developmental pathway is a key characteristic that differentiates deuterostomes from protostomes, where the blastopore typically develops into the mouth.

In deuterostomes, the formation of the anus from the blastopore allows for a specific embryonic development pattern that influences the organism's body plan. This group includes organisms such as echinoderms and chordates, which exhibit complex body structures and developmental processes. The deuterostome characteristic is fundamental for understanding evolutionary relationships and developmental biology, as it reflects a significant divergence in the embryonic development of different animal groups.

Recognizing this distinction in embryonic development is vital for studies in animal physiology and evolutionary biology, as it provides insight into the diverse adaptations and organizations of multicellular organisms.