Amphibians Amphibian diversity Anura frogs 4000 sp Caudata

Amphibians

Amphibian diversity • Anura (frogs, ~4000 sp. ); Caudata (salamanders, ~450 sp. ); Gymnophiona (caecilians, ~175 sp. )

Amphibian characteristics • • • Skin – permeable – respiration – mucous glands – poison glands biphasic lifestyle second hearing system unique retinal cells skull – paired occipital condyles – reduction/loss of bones short ribs declining populations ectotherms found near water

Caecilian characteristics • No limbs, reduced or absent girdles • Annuli • Solidified skull with – Eyes reduced/absent – Fusion of bones – Roofed, few/no fossa • Tentacle • Phallodeum Siphonops annulatus

Salamander characteristics • Tailed, most with four limbs, four digits on front limbs, five digits on hindlimbs • Aquatic, terrestrial/fossorial, arboreal • Breathe through lungs, gills, and/or skin • Sprawling gait • Large genome – 15 -90 pg (humans: 3 pg) • Diverse life cycles, reproductive modes --mostly internal fertilization

Frog characteristics Squat, tailless body Fused limb bones Hindlimbs > forelimbs Few vertebrae Terrestrial, arboreal, aquatic Great diversity of reproductive modes – Mostly external fertilization • Many species with protrusible tongue for feeding • • •

Reptile diversity • • • Turtles (Chelonia) 300 species Crocodiles, alligators, caimans (Crocodylia) 27 species Tuatara (Sphenodon) 1 -2 species Lizards, snakes, amphisbaenids (Squamata) 6000 species Birds (Aves) 9000 species

Reptile characteristics • Dry, scaly outer covering • Shelled eggs laid on land • Ectotherms

Turtle characteristics • Shell • Fused to ribs • Fused to vertebrae • Limb girdles lie inside ribcage • Jaws lack teeth • Terrestrial or aquatic •

Crocodylian characteristics • Alligators, caimans, crocodiles, gavials • Large – 1 -8 meters • Complex parental care • Top-end predators

Lizard characteristics • 6000+ species • 2 or 4 limbs, or limbless • Oviparous, viviparous, ovoviviparous • Terrestrial, aquatic, arboreal, fossorial

What is Herpetology? • The study of amphibians and reptiles • Greek root – Herpein: to creep – Herpeton: creeping animal • "To herp" (verb): to look for herps • "Herps" – Amphibians: frogs, salamanders, caecilians – "Reptiles": lizards, amphisbaenids, snakes, crocodylians, tuataras, turtles

Why study amphibians and "reptiles" together as a single group? • An evolutionary grouping? – Amphibians and reptiles closest relatives? • Shared characteristics? – E. g. , ectothermy • Tradition? – History

Diapsida

Why study amphibians and reptiles together as a single group? • An evolutionary grouping? – Amphibians and reptiles are not closest relatives • Shared characteristics? – E. g. , ectothermy? • Tradition? – History

Shared characteristics of reptiles and amphibians • Ectothermy – Thermoregulation – Energy requirements • • Body size and shape Lay eggs (most) Terrestrial (most) Lack fur and feathers…

Differences between reptiles and amphibians • • Amniotic egg Integument Claws Heart Skull Fertilization Moisture environment

Why study amphibians and reptiles together as a single group? • An evolutionary grouping? – Amphibians and reptiles are not close relatives • Shared characteristics? – Amphibians and reptiles differ greatly in anatomy and physiology • Tradition? – History

Why study amphibians and reptiles together? Tradition! "Most amphibia are abhorrent because of their cold body, pale colour, cartilaginous skeleton, filthy skin, fierce aspect, calculating eye, offensive smell, harsh voice, squalid habitation, and terrible venom; and so their Creator has not exerted his powers to make many of them. " Linnaeus (1750)

History of Herpetology Contributions to the History of Herpetology Kraig Adler; ssarherps. org • Aristotle (384 -322 BC): blood, locomotion, limbs, eggs • Carl Linnaeus (1707 -1778): Systema Naturae (1735+) • 1700 s-1800 s: France is center – G. L. L. Comte de Buffon (Histoire Naturelle 1749 -1804), B. Lacepede: Histoire des Quadrupedes Ovipares (1788), Histoire des Serpientes (1789) – A. Brongniart (1799): Separation of Batrachians (amphibians)/reptiles – F. Daudin: Histoire Naturelle des Reptiles (1802) – A. Dumeril and G. Bibron: Erpetologie Generale (1834 -54)

History of Herpetology • Mid-1800 s: Great Britain (J. Gray, A. Gunther, G. Boulenger) • Late 1800 s: North America emerges – J. Holbrook: North American Herpetology (1836 -42) – E. D. Cope: The Crocodilians, Lizards, and Snakes of North America (1900) – L. Stejneger: Herpetology of Puerto Rico (1904)

Doris Cochran 1898 -1968 Curator of Herpetology, Smithsonian 1942 -1968

Herpetology in the US today • UC Berkeley – C Camp, R Stebbins, D Wake, M Wake, H Greene, C Moritz, J Mc Guire • U of Kansas – E Taylor, J Tihen, H Smith, H Fitch, W Duellman, L Trueb, R Brown, R Glor • USNM (Smithsonian) – D Cochran, J Peters, G Zug, R Mc. Diarmid, R Heyer, K de Queiroz • UT Austin – F Blair, D Cannatella, D Hillis, E Pianka, M Ryan, C Gans • Harvard – T Barbour, A Romer, A Loveridge, E Williams, P Alberch, J Cadle, J Hanken, J Losos • American Museum of Natural History – M Dickerson, G Noble, C Bogart, C Myers, C Cole, D Frost

Herpetological societies • American Society of Ichthyologists and Herpetologists (ASIH; 1913; Copeia) • Herpetologists’ League (HL; 1946; Herpetologica, Herpetological Monographs) • Society for the Study of Amphibians and Reptiles (SSAR; 1958; Journal of Herpetology, Herpetological Review)

Web resources • • • Amphibiaweb. org reptile-database. org ssarherps. org asih. org herpetologistsleague. org Journal of Herpetology, Copeia, Herpetologica, Amphibia-Reptilia, Herpetological Conservation and Biology, Phyllomedusa…

Systematics • Phylogenetics • Taxonomy – Classification – Nomenclature