Herpetology: the Biology of Tetrapods BIOEE 470 and 472

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Herpetology the Biology of Tetrapods (BIOEE 470
and 472)
Do we need to order more Pough et al. (I will
put a copy on course reserve in Mann Library)?
If you are going to drop the lab, please do so
ASAP...
Calling male leaf rog (Phyllomedusa
sauvagii) PhotoH.W.Greene
Course website www.eeb.cornell.edu/herpetology/in
dex.html
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Herpetology the Biology of Tetrapods
Reading assignment Pough et al., Chapter 3
(the next several weeks will refer back to this
chapter, and there will be additional text
assignments) Vocabulary Osteichthyes,
Actinopterygii, Sarcopterygii, Tetrapoda,
Amphibia, Gymnophiona, Anura, Urodela,
Cryptobranchoidea, Cryptobranchidae, Hynobiidae,
Sirenidae, Salamandroidea, Plethodontidae,
Ambystomatidae, Dicamptodontidae, Amphiumidae,
Proteiidae, Rhyacotritonidae, Salamandridae,
Amniota, Mammalia, Reptilia, Testudines,
Lepidosauria, Archosauria, Crocodylia, Aves,
spermatophore, spermathecae, external gills,
larva, Den Master, Choanata, Dipnoi, Latimeria,
sublime, beauty, adaptation, exaptation,
Batrachia, crown-group, stem-group, granular
glands
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Herpetology the Biology of Tetrapods
Can you arrange Tetrapoda, Amphibia,
Gymnophiona, Batrachia, Anura, Urodela,
Cryptobranchoidea, Salamandroidea,
Plethodontidae, Ambystomatidae, and Amniota in
terms of branches, nodes, and one or more
adaptively important, diagnostic character
states? Are body elongation and limblessness
in caecilians a derived or retained primitive
trait? Can you discuss those two traits as
homoplasies among extant salamanders? Did the
earliest tetrapods have internal
fertilization? How would you use the insights
of Darwin and Kant to justify spending money and
other precious resources for the conservation of
hellbenders?
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Herpetology the Biology of Tetrapods
The primary emphasis in this course is
on Amphibia Gymnophiona (167
species) Urodela (516 species) Anura (4,810
species) Reptilia Testudines (300
species) Crocodylia (23 species) Rhynchoceph
alia (2 species) Squamata Lizards (3,000
species) Amphisbaenians (150
species) Snakes (2,700 species) But we need
to keep in mind Aves (8,700 species) Mammalia
(4,800 species) Actual total species now at
almost 6,000
So, almost 12,000 species in traditional
herpetology, about 25,000 tetrapods How are we
going to make sense of all of this diversity, and
what does it all mean?
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Why standardize names and arrange the units of
life?
So we can talk about them Timber Rattler,
Black Rattler, Eastern Yellow Rattlesnake,
Mountain Rattlesnake, Banded Rattlesnake, Velvet
Tail, Cascabel, Klapperschlange Crotalus
horridus So we can make sense of them deer,
long-horned beetle, crocodile, ant, wasp,
pelican, rat, rattlesnake, Green Frog...
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Naming organisms and groups...
Taxonomy naming organisms (taxon, plural
taxa) Systematics arranging names
(biologists, indigenous peoples (folk
taxonomy, etc.) Some familiar creatures Mus
domesticus, Ambystoma tigrinum, Chrysemys picta,
Rana pipiens, Canis lupus, Canis latrans, Canis
familiaris, Vulpes fulvus, Canidae NB
individual taxa are always singular, e.g., Canis
latrans is the coyote, but not Canis latrans
are common in Tompkins County
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More on naming organisms and groups...
Binomial nomenclature, as of Linnaeus
(1758)... Genus (plural genera) and species
are italicized, as in Boa constrictor Linnaeus
1758 and Corallus caninus (Linnaeus 1758) Type
specimens and type descriptions Taxonomic
priority English standard names an aquatic
coralsnake (not coral snake) versus the Aquatic
Coralsnake (Micrurus surinamensis)
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Traditional Classification
Reptilia
Mammalia
Kingdom Phylum Class Order Family
Genus Species
Aves
Osteichthyes
Chondrichthyes
Amphibia
This classification tells us almost nothing about
evolutionary relationships, but isnt that a
beautiful Copperhead!
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Traditional classification also
Ignores three of the most important events in the
evolution of vertebrates evolution of jaws
move on to land amniotic egg And, if wings are
so important, why dont we have Class Chiroptera?
Phylum Chordata Class Agnatha
Chondrichtyes Osteichthyes
Amphibia
Reptilia Aves Mammalia
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Family trees illustrate genealogy
European ancestors
English colonists
Spanish colonists
Abuela
Abuelo
Abuela
Abuelo
Grandma
Grandpa
Grandma
Grandpa
Madre
Padre
Mother
Father
Gerardo
Gabriela
Harry
Will
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Grouping species more words and concepts
shared derived characters (synapomorphy)
special similarity shared primitive characters
(symplesiomorphy) general similarity (we cant
distinguish someone from Somalia as a Somalian
by the presence of two legs!) monophyly one
ancestor and all of its descendants paraphyly
one ancestor and some but not all of its
descendants
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Phylogenetic groupings
Monophyletic includes an ancestor and all
descendents Paraphyletic includes ancestor and
some (but not all) descendents Polyphyletic
does not include the most recent common ancestor
of all taxa
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Grouping species words and concepts
descent with modification phylogeny,
phylogenetic tree, cladogram a branching diagram
of evolutionary history homology similarity
due to common ancestry homoplasy
independently evolved similarity (convergent
evolution, including reversals) in-group the
taxa under consideration out-groups their
successively more distant relatives
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• Homology or homoplasy? California ocotillo
  (left) and Madagascan allauidia (right)

Figure 15.11, Campbell et al. Biology Concepts
and Connections
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TAXA
Outgroup(Reptiles)
Ingoup(Mammals)
Eastern boxturtle
Duck-billedplatypus
Red kangaroo
North Americanbeaver
CHARACTERS
Long gestation
Gestation
Hair, mammary glands
Vertebral column
Long gestation
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Gestation
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Figure 15.13, A, Campbell et al. Biology
Concepts and Connections
Hair, mammary glands
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Vertebral column
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Phylogenetic Classification

• every grouping is monophyletic
• characters diagnose every named group
• each evolutionary transition is represented
• we can reconstruct the TREE!

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Phylogenetic classification of tetrapods
Tetrapoda (four limbs) Amphibia Amniota (lay
shelled eggs) Mammalia (hair) Reptilia (scaly
skin) Testudines (turtles) Sauria Lepido
sauria (lizards etc.) Archosauria (dinos
etc.) Crocodylia (crocs) Aves
(birds) (If you learn this, youve also learned
the phylogeny!)
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Reptilia Testudines Sauria
Lizards Snakes
Crocodiles
Sphenodon
Turtles
Birds
NB What are branches, nodes, and terminal taxa?
Which branch is basal?
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Reptilia Testudines Sauria
Lepidosauria Archosauria
Lizards Snakes
Crocodiles
Sphenodon
Turtles
Birds
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Reptilia Testudines Sauria
Lepidosauria Sphenodon Squamata
Archosauria Crocodylia Aves
Lizards Snakes
Crocodiles
Sphenodon
Turtles
Birds
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Reptilia Testudines Sauria
Lepidosauria Sphenodon Squamata
Archosauria Crocodylia Aves
Class Reptilia is paraphyletic!
Lizards Snakes
Crocodiles
Sphenodon
Turtles
Birds
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Reptilia Testudines Sauria
Lepidosauria Sphenodon
Squamata Archosauria Crocodylia Aves
Crocodiles
Lizards Snakes
Sphenodon
Turtles
Birds
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Phylogenetic Classification of Vertebrates
Gnathostomata (jawed vertebrates)
Chondrichtyes Osteichthyes Actinopterygii
Sarcopterygii Latimeria
Choanata Dipnoi
Tetrapoda Amphibia Gymnophiona
Batrachia Anura
Urodela Amniota Mammalia
Reptilia Testudines
Lepidosauria
Archosauria Crocodylia Aves
What? Are we all just bony fishes? NB
relative species richness of ray-finned and
fleshy-finned fishes (ca. 25,000 each) Why is
Latimeria italicized here? What is an
unresolved trichotomy?
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Would Linneaus (1758, Systema Naturae) have loved
an amphisbaenian?
These foul and loathsome animals have a single
ventricle and auricle, doubtful lungs, and a
double penis. Most are abhorrent because of cold
body, pale color, 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.
Giant Worm-lizard (Amphisbaena alba), Instituto
Butantan, Brazil (photosH.W.Greene)
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Is an Urutú beautiful?
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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Charles Darwin, in the closing lines of his 1859
Origin of Species
There is grandeur in this view of life that,
whilst this planet has gone circling on according
to the fixed law of gravity, from so simple a
beginning endless forms most beautiful and most
wonderful have been, and are being evolved.
Descent with modification, as in a tree of
life with taxa as branch tips and nodes as
ancestors
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Immanuel Kant on beauty and the sublime, from his
1790 Critique of Judgement
Kant The beautiful in nature concerns the
form of the object, which consists in the
objects being bounded, whereas the sublime is to
be found in the contemplation of objects that are
formless and unbounded and that strike the
imagination in a particularly powerful way
Beauty is a property of organisms, whereas the
sublime transcends individual characteristics
The sublime esthetics of organisms encompasses
their evolutionary relationships and natural
history
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More from Kant
The mathematically sublime applies to
magnitude, immensity, or sheer numbers (think of
the diversity of tropical frogs!)
Contemplation of violent storms, earthquakes, and
volcanic eruptions are examples Kant gives of
dynamically sublime experiences (think of a
really big crocodile!) Can we mix Darwin and
Kant, and speak of the phylogenetically sublime,
in the sense that evolutionary history enhances
esthetic appreciation?
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Keeping in mind Darwin and Kant, ponder these
amazing photographs
Which taxa youve learned thus far are shown
here? What kind of sublime is illustrated here?
Photos T.Jenkins USFWS
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Tailed frog
Spadefoots
Toads
Tree Frogs
Water Frogs
Can we speak of the phylogenetically sublime?
Triadobatrachus 245 mya