Herpetology: the Biology of Tetrapods BIOEE 470 and 472

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Herpetology the Biology of Tetrapods (BIOEE 470
and 472)
Sorry, please just a little more patience and
Ill have the exams back for you Thursday
meanwhile though, Ill be doubling whichever
midterm you do better on for your final exam
total What about the dichotomous key exercise,
worth 20 pts? Stay turned for that on Thursday
too
How many kinds of tetrapods can you see in this
FL scene? (photoH.W.Greene)
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Turtles are special!
Complex and unexpected behavior Clemmys
insculpta and how it finds worms to eat
Parental care in Kinosternon and Gopherus
Predatory behavior of Philadelphia
Geochelone They are vulnerable and threatened
for food and pet tradeironic, given so well
protected in nature, or is it? Bog Turtles
(Clemmys muhlenburgi) exemplify several
conservation issues
Bog Turtle hatching at Zoo Atlanta (PhotoH.W.Gree
ne)
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Bog Turtle Distribution Map
Sampling
locality
Could you define the words endemic and relictual
in terms of Bog Turtles?
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Status Northern and Southern populations- listed
as threatened 1997 Factors underlying decline
loss and fragmentation of highly specialized
habitat herbaceous sedge meadows and fens (open
canopy) mosaic of dry-pocket, saturated and
flooded areas popular in pet trade small and
attractive
Is there a future for Bog Turtles in our country?
How much would we sacrifice to know that there
are still Bog Turtles out there?
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I was wrong about marine turtles!
Green sea turtle (Chelonia mydas Honu in
Hawaiian) basking on the North Shore of 'Oahu,
near the historic town of Hale'iwa They usually
bask on abandoned beaches on the many tiny
islands, but can always be found at this popular
tourist site. There are signs warning that
visitors can be arrested or fined if they touch
or harass the Honu. These guys are definitely my
favorite of all traditional herps! Enjoy!
(Sara Byus, BIOEE 470 student who sent me this
photograph during the 2005 class)
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Archosauria
Crocodylia one of two living groups of
archosaurs Pterosaurs up to 13 m wingspan,
4th finger supports wing Dinosauria
Ornithischia (ceratopsians etc.) and Saurischia
(Sauropodomorpha and Theropoda T. rex,
Velociraptor) Even if Aves isnt a clade
within theropod dinosaurs, birds are archosaurs
and all that implies!! How many times has
powered flight evolved within amniotes?
American Alligator, Alligator mississippiensis,
Wakulla Springs, FL (photoH.W.Greene)
American Rhea, Pantanal, Brazil
(photosH.W.Greene)
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Crocodylia
23 species of living crocodylians (or
crocodilians?) Aquatic adaptations in a
primitively terrestrial group tail shape,
elevated eyes and nostrils, soft tissue valve at
back of throat Why are there no fully marine
crocs and so few fresh water mammal analogs
(e.g., there are no 20 foot-long otters)?
Dwarf Caiman (Paleosuchus palpebrosus)
Brazil (photoH.W.Greene)
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Crocodylia locomotor diversity
Sprawling locomotion? Effective swimmers
High walk Galloping Incredible jumpers
Pp. 361-362, Pough et al.
Yacare Caiman, Pantanal, Brazil (photoH.W.Greene)
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Crocodylia reproduction and social behavior
Complex vocalizations, visual displays, etc.
Eggs in constructed mound nests or burrows
Parental care (nest opening, transport and even
feeding of young) The above traits are shared
with birds and other dinosaurs, i.e., they are
evidently derived traits of archosaurs as a
group Turtles, snakes, and other organisms
are often commensals in crocodylian nests Pp.
345-346 and 481-485, Pough et al.
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Crocodylia feeding biology
Diet and ontogeny Diet generalization and
specialization Spin and shear, communal
feeding (stay tuned!) Strategic decomposition
and lithophagy Read pp. 398-400 in Pough et al.
Yacare Caiman, Brazilian Pantanal (PhotosH.W.Gree
ne)
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Taxonomy and snout shapes Alligatoridae
Always with broad snouts and 4th lower tooth
hidden in upper jaw socket Gators are
relatively friendly (although caimans arent!)
Freshwaters in China and the New World
Well differentiated genetically, thus ancient
divergence and relict distributions (e.g.,
Chinese and North American Alligators,
neotropical caimans)
Upper, Black Caiman (Caiman niger), middle and
lower, American Alligator (Alligator
mississippiensis) Upper photoM.P.Fogden
middleR.Overstreet bottomH.W.Greene
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Taxonomy and snout shapes Crocodylidae
Usually narrow snout and 4th tooth always
visibly exposed alongside upper jaw Crocodiles
are unfriendly, so use binoculars to check 4th
lower tooth condition in all wild crocodylians!
Weakly differentiated genetically,
euryhaline, and cosmopolitanthus recent and
widespread dispersal In the New World
American (C. acutus), Cuban (C. rhombifer), and
Orinoco Crocodiles (C. intermedius)
Crocodylus sp. (PhotoH.W.Greene)
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Taxonomy and snout shapes Gavialidae
Two species whose relationships have been so
controversial that Tomistoma schlegelii has been
called the False Gharial Gharials (gavials)
have long snouts that perhaps function for
plucking fish Endemic to Asia An African
true crocodile (Crocodylus cataphractus) is
convergent in having a long slender snout
Gavialis gangeticus (PhotoM.P.Fogden)
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Crocodylian taxonomy what are these?
African Dwarf Crocodile (Osteolaemus) and South
America Dwarf Caiman (Paleosuchus)
Upper photoH.W.Greene lower photoM.Martins
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Crocodylians and humans
Two species of Crocodylus eat humans regularly,
and other big crocodylians do so occasionally (6
U.S. fatalities between 1973-1988 from wild
alligators) New Caldedonian Mesosuchus was
terrestrial, basal to all living crocodilians,
and found in cooking middens 1640 ybp
Alligator mississippiensis seriously endangered
by the 1960s, but now so common it is legally
harvested in several states, and crocodiles are
ranched for leather in Africa, Asia, and South
America
Not an American Alligator that had eaten a FL
golfer, as sometimes claimed, but a Crocodylus
porosus, probably in Australia, that had indeed
eaten a human (source unknown, widely circulated
on the www)
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Kant and the dynamically sublime Nile Crocodiles
and Hippos
(All photosL.M.Chan)
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Kant and the phylogenetically sublime American
Alligators gang up on fish
When you go see alligators and crocodiles in
FLand you really should do this dont think
turtles and lizards, think dinosaurs and
birds!
Alligator mississippiensis, Paines Prairie, a
public park near Gainesville, FL
(PhotosH.W.Greene)