BIOL 321 Lecture Notes - Lecture 21: Arthropod Cuticle, Arthropod, Sister Group
Document Summary
Preamble: highly successful" by any metric (but there are different ways to measure success, food webs- aquatic and terrestrial. Important for any ecosystem you can think of: medical importance- all of these diseases transferred by mosquitos, economic importance (agriculture) Many crops rely on insect pollinators: model organisms for basic research- foremost example is drosophila, phylogenetic controversies. Narrowed down to few suspects but still controversial. One of the most extensively debated subjects in evolutionary biology has been the origin of the arthropods -f. r. Each one gives rise to a pair of appendages. These two groups supposedly developed metamerism independent of each other. Tagmosis- grouping of multiple adjacent metameres into coherent morphological units (tagmata) having specialized functions. Insects have 3 body tagmata (head, thorax, abdomen) and each tagma consists of multiple metameres: exoskeleton. Largely consists of chitin polysaccharides and protein. Exoskeleton is secreted by the epidermal epithelium.