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Dermoptera & CHIROPTERA Evolution & Systematics of a highly successful Order EEOB 625 28 January 2004 Order Dermoptera • Archonta: a monophyletic group (?) incluiding Insectivora, Dermoptera, Chiroptera, & Primates • Dermoptera: skin-winged from neck to near ends of digits with recurved claws • Cynocephalidae: 2 species in Oriental feed on leaves, flowers, fruit, & tree sap • Specialized incisors • Convergent with Orders _____, ______, _____ ? Cynocephalidae Origin & Evolution of Chiroptera • Early derivative of Insectivores • Icaronycteris index: fossil of Eocene, few primitive features (not a “missing link”) • Relationship to birds & insects: partitioning of the aerial insect resource • Examples of convergence and coevolution: how many can you name? Adaptive Zone of Chiroptera • Powered flight, nocturnal, insectivorous, • • • • _________, __________, _________ Nutritional strategies of bats: diverse feeding habits (928 niches), energetics of flight, Daily torpor and hibernation Reproductive patterns: delayed fertilization, nursing & nursery colonies How does all of this explain the success of bats or relate to the chiropteran adaptive zone? Evolution of Flight in Bats • Preadaptation of insectivore ancestors for flight? Arboreal ancestors, using to echolocation to prey on (flying) insects • Volant & powered flight compared: +/- of each • Volant (here = gliding) locomotion in many taxa but powered flight is a rare breakthrough ____? • Did powered power flight evolve from gliders? • Evidence: morphological changes in the shoulder and hand, but why is the hand of gliders not modified? Suborder Megachiroptera • What does suborder designation suggest about the phylogeny of an order? • Is Chiroptera a monophyletic order? • Megachiroptera & Microchiroptera compared • Is Megachiroptera more closely related to primates, as suggested by their vision (and nutritional strategies?), or to a common flying ancestor with echolocation secondary? • How do we weigh different types of evidence? Phyllostomidae Neotropical only: Lower in species richness but high in adaptive radiation