Herpetology: the Biology of Tetrapods BIOEE 470 and 472

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Herpetology the Biology of Tetrapods (BIOEE 470
and 472)
Be sure to return your exam to me if you
deserve points added on the last question Be
sure to sign up for the Bronx Zoo trip if you
intend to go Start thinking about the exam on
April 26th we will have guest lectures on the
12th, 17th, and 19th, and Ill be sending you
practice exam questions etc. over the next week
by email!
Why does this Tropical Milksnake (Lampropeltis
triangulum) have such bright colors?
(photoM.P.Fogden)
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Themes in Snake Evolution Venoms
See pp. 420-425 in Pough et al. (previously
assigned) Increased flexibility of the
colubroid palatomaxillary arch freed up the
maxilla for prey specialization Inner tooth
rows (on left and right palatine and pterygoid
bones) retain their role for ingestion Only in
colubroids is there much differentiation of
maxillary teeth in some cases, venom
African egg-eating snake (Dasypeltis) PhotoM.P.F
ogden
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Is an Urutú beautiful?
The expression on this snakes face was hideous
and fierce I do not think I ever saw anything
more ugly (Charles Darwin) We will only
conserve what we love, we will only love what we
understand, and we will only understand what we
are taught (Baba Dioum, Senegalese
conservationist)
Urutú (Bothrops alternatus) Brazil
(photosH.W.Greene)
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What about humans and snakes?
Why do we have such ambivalent, even polarized
responses to snakes? This is a subsistence
hunter in Colombia with a 22-foot-long Anaconda
(Eunectes notaeus)
(PhotoW.W.Lamar)
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What is it about humans and snakes?
Tarsiers, Old and New World monkeys, and humans
eat snakes Snakes eat tarsiers, lemurs,
monkeys, gibbons, and people
(PhotoC.Niemitz)
26 of 120 Agta males had survived python
attacks and they knew of six fatalities (Headland
Greene unpubl.) Ambivalence about snakes has
ancient roots, but is also shaped by individual
experience education!
(Photo J. Headland)
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Field studies of Black-tailed Rattlesnakes
gt15 years, gt4,000 observations of 50 Crotalus
molossus Chiricahua Mountains, Cochise County,
AZ (N of Mexico and W of NM
(Upper photoD.L.Hardy Sr. Lower
photoM.P.Fogden)
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Field studies of Black-tailed Rattlesnakes
Captured gently, anesthesized, and implanted
with radio transmitters Observed for up to 12
years
(Upper and lower photosM.P.Fogden
middleD.L.Hardy Sr.)
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Field studies of Black-tailed Rattlesnakes
Telemetry lets one find snakes even in
unexpected places! Feed entirely on mammals,
with woodrats and bunnies their staples Males
search for and fight over females during brief
mating season
(Upper photoH.W.Greene lowerD.L.Hardy Sr.)
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Field studies of Black-tailed Rattlesnakes
Direct observations revealed surprising
phenomena Pitvipers have parental care,
female remains with babies for 6-10 days, until
after they shed natal skin
(PhotosD.L.Hardy Sr.)
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Field studies of Black-tailed Rattlesnakes
The minds of snakes? Male 41 altered a
hunting site to his advantage, using combat
behavior against a dead fern frond What
would a female or a naïve male do?
(PhotoH.W.Greene)
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What about the future of snakes?
Timber Rattlesnakes (Crotalus horridus) are
endangered in the Northeast These are NOT bird
watchers!
(Upper photoM.P.Fogden othersH.W.Greene)
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Appreciating giant snakes
Left photoH.W.Greene, right photoJ.Rivas