How to build a tree with the evolutionary relationships among animals B) Comb jelly Mnemiopsis leidyi (about 2 inches long) swimming in the water (by Bruno Vellutini, Wikimedia Commons). Figure 1:A) Tubular yellow sponge Aplysina fistularis (about 20 inches tall) in the ocean floor (by Timothy Brown, Wikimedia Commons). The debate is still ongoing, but research efforts have generated exciting new knowledge about our early origins and about the complexity of animal evolution. 1B), instead of sponges, were the first branch in the animal tree (see Fig. However, in 2008, a group of scientists proposed a controversial hypothesis in which comb jellies (Fig. 1A) and on the other, a branch that later gave rise to all other animals (see Fig. The traditional view is that the ancestor of all animals was possibly sponge-like and that it gave rise to two descending branches in the animal tree of life: on one side sponges (Fig. To answer it, we need to know how modern animals are related to each other, what order they appeared in, and what evolutionary changes resulted in the diversity we see today. If we could travel back in time 540 million years, what would the first animals look like? This is one of the longstanding questions scientists aim to answer in the study of how animals evolved and became distinct from their unicellular relatives.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |