Amphibian diversity Anura frogs 4000 sp Caudata salamanders 450 sp Gymnophiona caecilians 175 sp Skin permeable respiration mucous glands poison glands biphasic lifestyle ID: 232694
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Slide1Slide2
AmphibiansSlide3
Amphibian diversity
Anura
(
frogs, ~4000 sp.);
Caudata (salamanders, ~450 sp.); Gymnophiona (caecilians, ~175 sp.)Slide4
Skin
permeable
respiration
mucous glands
poison glands
biphasic
lifestylesecond hearing systemunique retinal cellsskullpaired occipital condylesreduction/loss of bonesorientation of stapesshort ribsdeclining populations
Amphibian characteristicsSlide5
Caecilian characteristics
No limbs, reduced or absent girdles
Annuli
Solidified skull with
Eyes reduced/absentFusion of bones
Roofed, few/no fossa
TentaclePhallodeumSiphonops annulatusSlide6
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: 3pg)Diverse life cycles, reproductive modes --mostly internal fertilizationSlide7
Frog characteristics
Squat, tailless body
Fused limb bones
Hindlimbs
> forelimbs
Few vertebrae
Terrestrial, arboreal, aquaticGreat diversity of reproductive modesMostly external fertilizationMany species with protrusible tongue for feedingSlide8
Reptile diversity
Turtles (
Chelonia
) 300 species
Crocodiles, alligators, caimans (Crocodylia) 27 speciesTuatara (
Sphenodon
) 1-2 speciesLizards, snakes, amphisbaenids (Squamata) 6000 speciesBirds (Aves) 9000 speciesSlide9
Reptile characteristics
Dry, scaly outer covering
Shelled eggs laid on land
EctothermsSlide10
Turtle characteristics
Shell
Fused to ribs
Fused to vertebrae
Terrestrial or aquatic
Limb
girdles lie inside ribcageJaws lack teeth Slide11
Crocodylian
characteristics
Alligators, caimans, crocodiles, gavials
Large
1-8 meters
Complex parental care
Top-end predatorsSlide12
Lizard characteristics
6000+ species
2 or 4 limbs, or limbless
Oviparous, viviparous, ovoviviparous
Terrestrial, semiaquatic, arboreal, fossorialSlide13Slide14
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, turtlesSlide15
Why study amphibians and "reptiles" together as a single group?
An evolutionary grouping?
Amphibians and reptiles
closest
relatives?Shared characteristics?E.g.,
ectothermy
?Tradition?HistorySlide16
DiapsidaSlide17
Why study amphibians and reptiles together as a single group?
An evolutionary grouping?
Amphibians and reptiles are not
closest
relativesShared characteristics?E.g.,
ectothermy
?Tradition?HistorySlide18
Shared characteristics of reptiles and amphibians
Ectothermy
Thermoregulation
Energy requirements
Body size and shape
Lay eggs (most)
Terrestrial (most)Lack fur and feathers…Slide19
Differences between reptiles and amphibians
Amniotic egg
Integument
Claws
Heart
Skull
FertilizationMoisture environmentSlide20
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?HistorySlide21
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)Slide22
History
of
Herpetology
Contributions to the History of Herpetology
Kraig Adler; ssarherps.org
Aristotle (384-322 BC): blood, locomotion, limbs, eggs
Carol Linnaeus (1707-1778): Systema Naturae (1735+)1700s-1800s: France is centerG. Buffon: Histoire Naturelle (1749-88)B. Lacepede: Histoire des Quadrupedes
Ovipares et des Serpientes
(1789)
A.
Brongniart
(1799): Separation of Batrachians (amphibians)
F.
Daudin
:
Histoire
Naturelle
des Reptiles
(1802)
A.
Dumeril
and G.
Bibron
:
Erpetologie
Generale
(1834-54)Slide23
History of Herpetology
Mid-1800s: Great Britain (J. Gray, A. Gunther, G. Boulenger)
Late 1800s: 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)Slide24
Doris Cochran 1898-1968
Curator of Herpetology, Smithsonian 1942-1968Slide25
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 GlorUSNM (Smithsonian)D Cochran, J Peters, G Zug, R McDiarmid, R Heyer, K de QueirozUT 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 FrostSlide26
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)Slide27
Web resources
Amphibiaweb.org
reptile-
database.org
ssarherps.orgasih.orgherpetologistsleague.orgSlide28
Journals
Journal of Herpetology,
Copeia
,
Herpetologica, Amphibia-Reptilia, Herpetological Conservation &Biology, Herpetology Notes, Phyllomedusa, Journal of Mesoamerican Herpetology, African Journal of Herpetology,
Salamandra
, Herpetological Monographs, Chelonian Conservation &Biology…Slide29Slide30
Systematics
Phylogenetics
Taxonomy
Classification
NomenclatureSpecies and higher level taxaSlide31
Species concepts
Phenetic
species concept
: A species is a set of organisms that look similar to each other and distinct from other sets (Ridley, 1993).Slide32
Species concepts
Phenetic
species concept
: A species is a set of organisms that look similar to each other and distinct from other sets (Ridley, 1993).
Ecological species concept: A species is a set of organisms exploiting (or adapted to) a single niche (Ridley 1993)
.Slide33
Species concepts
Phenetic
species concept
: A species is a set of organisms that look similar to each other and distinct from other sets (Ridley, 1993).
Ecological species concept: A species is a set of organisms exploiting (or adapted to) a single niche (Ridley 1993)
.
Biological species concept: Species are groups of actually or potentially interbreeding natural populations, which are reproductively isolated from other such groups (Mayr, 1940). Slide34
Species concepts
Phenetic
species concept
: A species is a set of organisms that look similar to each other and distinct from other sets (Ridley, 1993).
Ecological species concept: A species is a set of organisms exploiting (or adapted to) a single niche (Ridley 1993)
.
Biological species concept: Species are groups of actually or potentially interbreeding natural populations, which are reproductively isolated from other such groups (Mayr, 1940). Evolutionary species concept: A species is a single lineage of ancestor-descendant populations which maintain its identity from other such lineages and which has its own evolutionary tendencies and historical fate (Wiley, 1981). Slide35
Species concepts
Phenetic
species concept
: A species is a set of organisms that look similar to each other and distinct from other sets (Ridley, 1993).
Ecological species concept: A species is a set of organisms exploiting (or adapted to) a single niche (Ridley 1993)
.
Biological species concept: Species are groups of actually or potentially interbreeding natural populations, which are reproductively isolated from other such groups (Mayr, 1940). Evolutionary species concept: A species is a single lineage of ancestor-descendant populations which maintain its identity from other such lineages and which has its own evolutionary tendencies and historical fate (Wiley, 1981). Phylogenetic species concept: A species is the smallest diagnosable cluster of individual organisms within which there is a parental pattern of ancestry and descent (Cracraft 1983).Slide36
Species concepts: History
Pre-1942
Typology
Key reading: Aristotle
1940s-1990sOperationalismInterbreedingKey reading: Mayr
1942
1990s-nowSpecies = evolutionary lineages (Simpson1961)Operational/conceptual distinctionKey reading: Wiley 1981, de Queiroz 1998, Frost and Kluge 1994 Slide37Slide38Slide39Slide40Slide41