exoskeleton
Yes they do. Echinoderms, which include starfish, and chordates, which include humans are closely related in an evolutionary sense due to the way their embryos are formed in the early stages of development. Once past that point, the very obvious differences form.
Echinoderms and deuterostomes share a fundamental evolutionary relationship, as echinoderms are a subgroup within the deuterostome clade. This indicates that both groups, along with chordates and hemichordates, share a common ancestor, highlighting their evolutionary link. Deuterostomes are characterized by their embryonic development, where the anus forms before the mouth, a feature that distinguishes them from protostomes. This shared developmental pattern suggests that echinoderms and deuterostomes have diverged from a common lineage, influencing their anatomical and physiological traits.
Echinoderms are considered closely related to chordates due to their shared developmental features, such as the presence of a deuterostome developmental pattern, where the anus forms before the mouth during embryonic development. Additionally, both groups exhibit similarities in their genetic and molecular structures, particularly in their Hox gene arrangements. These characteristics suggest a common evolutionary ancestor, highlighting the evolutionary connection between echinoderms and chordates.
Echinoderms, such as starfish and sea urchins, are considered closely related to chordates, including corals, due to their shared evolutionary lineage within the deuterostomes, a major group of animals characterized by specific developmental features. Both echinoderms and chordates exhibit bilateral symmetry at some stage of their development and share common genetic and embryological characteristics. Moreover, molecular studies have shown significant genetic similarities between these groups, supporting their close evolutionary relationship.
Different morphological characterisitcs and different evolutionary biology. Sunflower seastars and insects belong to two different groups, echinoderms and arthropods, respectively.
Zoologists believe that pentaradial symmetry was not present in the ancestor of echinoderms because this symmetry is a derived characteristic that evolved later in their evolutionary history. The ancestral echinoderms likely exhibited bilateral symmetry, similar to their closest relatives, such as chordates and other deuterostomes. Fossil evidence and comparative studies of living echinoderms suggest that the transition to pentaradial symmetry occurred after the divergence from their bilateral ancestors, as a response to their marine environments and ecological adaptations.
Yes, larvae as a developmental stage evolved before starfish. The evolutionary lineage leading to echinoderms, which includes starfish, is believed to have diverged from common ancestors of other animal groups over 500 million years ago. Larval forms in marine organisms, including echinoderms, represent an ancient evolutionary strategy for dispersal and survival in the ocean. Thus, the concept of larval stages predates the specific evolution of starfish.
Echinoderms are in the Animalia kingdom.
The scientific name for Echinoderms is Echinodermata.
Echinoderms belong to the phylum Echinodermata.
As of yet, there is no known species of parasitic echinoderms.
Yes Eventually echinoderms do live in water.