title: Bacterial influences on animal origins.
abstract: Animals evolved in seas teeming with bacteria, yet the influences of bacteria on animal origins are poorly understood. Comparisons among modern animals and their closest living relatives, the choanoflagellates, suggest that the first animals used flagellated collar cells to capture bacterial prey. The cell biology of prey capture, such as cell adhesion between predator and prey, involves mechanisms that may have been co-opted to mediate intercellular interactions during the evolution of animal multicellularity. Moreover, a history of bacterivory may have influenced the evolution of animal genomes by driving the evolution of genetic pathways for immunity and facilitating lateral gene transfer. Understanding the interactions between bacteria and the progenitors of animals may help to explain the myriad ways in which bacteria shape the biology of modern animals, including ourselves.
authors.affiliation: Department of Oceanography, Center for Microbial Oceanography: Research and Education, Sea Grant College, University of Hawai'i Mānoa, Honolulu, Hawaii 96822.
authors.forename: Rosanna A
authors.initials: RA
authors.lastname: Alegado
authors.affiliation: Howard Hughes Medical Institute and the Department of Molecular and Cell Biology, University of California, Berkeley, California 94720.
authors.forename: Nicole
authors.initials: N
authors.lastname: King
mesh_terms: D000818:Animals; D001419:Bacteria / Q000235:genetics* / Q000378:metabolism; D005075:Biological Evolution; D002448:Cell Adhesion; D056897:Choanoflagellata / Q000235:genetics / Q000502:physiology*; D056890:Eukaryota / Q000235:genetics / Q000502:physiology; D010587:Phagocytosis; D010802:Phylogeny; D015398:Signal Transduction