Zoology Exam 4 Flashcards
(98 cards)
1
Q
Most distinctive turtles
A
Meiolaniidae
2
Q
Most terrestrial turtles
A
tortoises
3
Q
Name of turtle’s upper shell
A
carapace
4
Q
Name of turtle’s lower shell
A
plastron
5
Q
Function of plastron
A
allow the front and rear lobes to be pulled upward to close the openings of the shell
6
Q
The extant turtles
A
Cryptodires
Pleurodires
7
Q
Retract their head into their shell by bending the neck in a vertical S shape
A
cryptodires
8
Q
Retract their heads by bending the neck horizontally
A
Pleurodires
9
Q
Marine turtles are _________
A
cryptodires
10
Q
Characteristics of Turtles
A
• Turtle shell composed of upper carapace and lower plastron.
• All turtles lay eggs.
• No turtle exhibits parental care of offspring.
• Turtles have specialization for terrestrial, freshwater, and
marine environments.
• Most turtles are long-lived with poor capacity for rapid
population growth.
• For some species, sex of offspring is determined by
temperature.
11
Q
Currently accepted hypothesis about skull of turtles
A
diapsid origin
12
Q
Characteristics of carapace
A
• Epidermal and bone origins.
13
Q
Characteristics of plastron
A
Dermal ossifications.
Entoplastron and epiplastra
14
Q
Characteristics of turtle shell
A
• Hinges may be present in shell.
• Kinetic shell.
• Occurrence of hinges may be sexually dimorphic.
• Kinetic shell evolved independently multiple times.
• Ribs external to girdles.
• Extant turtles have 8 cervical vertebrae and 10 trunk
vertebrae.
• Articulations of cervical vertebrae permit bending of neck.
15
Q
Chracterstics of Shell and Skeleton of Cryptodires
A
- Ginglymes permit vertical rotation
* Have two sacral vertebrae
16
Q
Chracterstics of Shell and Skeleton of Pleurodires
A
• Use ball-and-socket or cylindrical joints between cervical
vertebrae.
• Have pelvic girdle fused to the carapace with a less distinct
sacral region.
17
Q
Characteristics of Turtle heart.
A
• Has ability to shift blood between pulmonary and systemic
circuits.
• Accomplished by having two continuous ventricular
chambers.
• Three subcompartments: cavum pulmonale, cavum
venosum, and cavum anteriosum.
18
Q
Characteristics of Turtle respiration.
A
Large, dorsal lungs.
Changes in pressure
• Thus, both inhalation and exhalation require muscular
activity.
• In and out movements of forelimbs and soft tissue of shell
conspicuous during respiration.
• Respiration without need for ribs may have contributed to
evolution of shell.
19
Q
In the respiration of Turtles, changes in pressure are a result of?
A
• Changes in pressure result of:
• Contracting muscles that move visceral organs upward,
compression lungs.
• Contracting muscles increase volume of visceral cavity
causing visceral organs to lower.
20
Q
The characteristics of of lungs of turtles
A
• Attached to carapace dorsally and laterally.
• Ventrally, lungs attached to non-muscular connective tissue
of the visceral organs.
•Weight of visceral organs pull on connective tissue.
21
Q
What are the patterns of Circulation and Respiration
A
Turtles exhibit right-to-left intracardiac shunt
•When resistance is the same in both pulmonary and system
circuit, deoxygenated blood may bypass lungs and flow into
systemic circuit.
• Function of shunt may be to match lung ventilation with
pulmonary gas flow.
• Shunt may stabilize oxygen concentration in blood.
• Shunt may reduce blood flow during breath holding to
permit more effective use of oxygen stored in lungs.
22
Q
What is the relationship between thermoregulation and body suze?
A
Large Body Size
• Contributes to thermal inertia.
• Slows rate of heating and cooling.
• At small body sizes, temperature regulation more difficult.
• Because of their large size, many marine turtles obtain some
degree of endothermy.
• Evidence of counter-current exchange mechanism in
flippers.
23
Q
Often used by turtles in social encounters.
A
Mechanosensory, visual, and chemosensory signals
24
Q
primarily used by males
against males and sometimes females.
A
Mechanosensory stimulation
25
Courtship of tortoises
1. Some tortoises have glands that enlarge during breeding
season and produce pheromones.
2. Head movements may function as social signal in some
tortoises.
3. Vocalization
26
Describe the Nesting behavior of turtles
1. All turtles are oviparous.
2. Female turtles use hind limbs to dig nest in sand or soil and deposit eggs
3. Some eggs deposited in late summer or fall and exhibit
diapause during winter.
4. Resume development when temperatures increase in spring.
27
Environmental Effects on Egg Development
1. Temperature, moisture, and gas concentrations can influence
turtle development.
2. Temperature can determine sex of embryo.
28
Temperature can determine sex of embryo in what way?
1. Higher temperatures usually result in females.
| 2. Lower temperatures usually result in males.
29
Used by turtles navigating between feeding and breeding habitats
Visual landmarks, sun orientation, chemical cues,
| mechanosensory cues, and magnetism
30
Navigation and Migration in Marine Turtles
• Most carnivorous.
• Males remain offshore for courtship and mating.
• Females come ashore to deposit eggs.
• Evidence for light, wave direction, and magnetism in
navigation.
31
Describe conservation of turtles.
* Many species produce few offspring.
* Habitat loss, especially for nesting can be catastrophic.
* Increasing occurrence of turtle diseases.
32
Characteristics of Lepidosaurs
• Integument covered with scales impermeable to water.
• Outer layer of epidermis shed periodically.
• Most have four appendages, but many have secondarily lost
appendages.
• Characterized by transverse cloaca and intervertebral
breakage zones.
33
Sister group to lizards and snakes
Tuatara
34
Derived from lizards
snakes
35
Characteristics of Tuatara
* Adult tuatara reach length of 60 cm.
* Both males and females territorial.
* Tuatara nocturnal with low body temperatures.
* Jaws and teeth produce shearing effect.
36
Major lineages of squamates
* Iguania
| * Scleroglossa
37
characteristics of lizards
• Range in size from 3 cm to 3 m.
• 80% of lizards weigh less than 20 g.
• Most large lizards are herbivores.
• Most constrained by conflict between locomotion and
respiration.
• Limb reduction or loss has evolved independently more
than 60 times.
• Leglessness usually associated with life in dense grass or shrubbery where slim, elongate body can better
maneuver.
38
Characteristics of Amphisbaenians digging lizards (fossorial).
• Rigid skulls used for tunneling.
• Single median tooth in upper jaw
• Nippers can remove small pieces of tissue.
• Integument characterized by annuli (rings).
• Not connected to trunk.
• Forms tube that body capable of sliding forward or
backward inside.
• Some species have blunt heads.
• Others have vertically or horizontally keeled snouts.
39
Ancestral condition of snakes represented by?
Scoecophidia
40
Scoecophidia characteristics?
* Three families of burrowing snakes.
* Possess vestigal pelvic girdle.
* Braincase resembles most snakes.
41
Origin of Snakes
• Evolved from subterranean lineage of “lizards” with
reduced eyes.
• Surface dwelling redeveloped later.
• Eyes of snakes different from that of lizards.
42
Two-thirds of extant snakes belong to?.
Colubroidea.
43
Characteristics of Colubroidea?
* Chemosensation important for many species.
* Tongue projected and waved in air or contact ground.
* Chemicals transferred to vomeronasal organs.
44
Characteristics of Sea snakes?
* 50 marine species.
* All marine species are venomous.
* Tail flattened.
* One lung reduced or absent.
* Gallbladder posterior to liver.
* Right kidney anterior to left kidney.
* Paired gonads may be displaced.
45
Sea Snake Respiration
* Nostrils located dorsally.
* Single lung extends to cloaca.
* Modified trachea.
* Capable of cutaneous respiration.
46
Sea snakes feed on what?
primarily fish
47
Describe Snake locomotion
* Lateral undulation.
* “Serpentine” locomotion.
* Body thrown into series of irregular curves.
48
Types of snake locomotion
Sidewinding
Concertina
rectilinear
49
Foraging
* Changes in temporal fenestration.
* Loss of lower temporal bar and quadratojugal bone.
* Changes contribute to increasing skull kinesis.
* Complete lower temporal arch present.
50
Changes in foraging
• Gap between quadrate and jugal widened.
• Suture between frontal and parietal bones became
straighter and more hinge-like.
• Quadrate became more mobile with development of
flexible connection between quadrate and squamosal.
• Condition called streptostyly.
51
Feeding of snakes
• Snakes generally swallow prey head first to allow limbs to
press against body
• Mandibular and pterygoid teeth of one side of the head
anchor prey while head is rotated to advance opposite
jaw.
• After prey has reached esophagus, neck muscles contract
to move prey to stomach.
• Most snakes eat prey while it is still struggling.
52
allow snakes to consume large prey without injury.
Constriction and venom are predatory specializations
53
Two hypotheses about what kills constricted prey:
• Prey suffocates because it is unable to expand thorax
for inhalation.
• Increased internal body pressures interrupt and stop
heart from beating.
54
Three categories of venomous snakes recognized
Opisthoglyphous, proteroglyphous, and solenoglyphous.
55
Feeding Specializations in Snakes
• Many species of snakes have enlarged teeth on maxillae.
3. Some species have lost ability to produce venom and
secondarily developed specializations for constriction.
4.Some snakes have a Duvernoy’s gland which is capable of
producing toxins that immobilize prey.
5. Evolution of venom capable of killing prey may have
allowed snakes to reduce need for constriction and
become specialized for rapid locomotion.
6.
56
Morphological Specializations of Constrictors
• Tight loops made possible by having short vertebrae
and trunk muscles that only span a few vertebrae.
• Tradeoff is that specialization for tight loops limits speed
of locomotion.
57
• Opisthoglyphous
• One or more enlarged teeth at rear of maxilla.
• Teeth may be solid or with groove to conduct saliva into
wounds.
58
Proteroglyphous
* Hollow fangs at front of maxilla.
| * Fangs short and permanently erect.
59
Characteristics of Solenoglyphous snakes for consuming
| larger prey:
• Triangular head reflects outward extension of skull.
• Quadrates at rear of skull are wide-spread allowing large
objects to pass through mouth.
• Adaptations do not appear to inhibit locomotion.
60
• Foraging Range of Strategies
Sit-and-wait Predators
• Cruising Forager (Intermediate)
• Widely Foraging Predators
Sit-and-wait predators primarily iguanians.
• Widely foraging predators primarily scleroglossans.
61
• Cruising Forager
* Cruising Forager
* Morphology, Physiology, and Behavior Intermediate
* Probably Represents Ancestral Condition
62
Morphology of Sit-and-Wait Predators
Stout bodies, short tails, and often cryptically colored.
• Blotches of pigmentation may be used to disrupt body
outline.
• Tail may be lost as predator avoidance mechanism
63
Physiology of Sit-and-Wait Predators
Move in brief, but rapid, bursts.
• Supported by anaerobic metabolism.
• Glycogen stored in muscles, but rapidly exhausted.
• Lactic acid inhibits metabolism.
64
Behavior of Sit-and-Wait Predators
Remain in one spot for an extended period.
• Survey environment, looking for insects.
• Capture prey by short, rapid movements.
• Vulnerable to actively searching predators.
65
Morphology of Widely Foraging Predators
Slim bodies, long tails, and often characterized by stripes.
| • Tail may be lost as predator avoidance mechanism.
66
Physiology of Widely Foraging Predators
* Move continuously at a reduced pace.
* Supported by aerobic metabolism.
* Larger hearts and more red blood cells.
* Capable of sustained activity for an extended period.
67
• Behavior of Widely Foraging Predators
Regularly move through environment and search for prey.
• Detect insects by chemical cues.
• Vulnerable to sit-and-wait predators!
68
• Squamate Social Behavior
Use visual, auditory, chemical, and tactile signals in
maintaining territories and selecting mates.
• Iguanians primarily use visual signals.
• Scleroglossans use pheromones extensively
69
Lizard Social Behavior
Male Anolis sp. lizards (iguanian) have gular fans.
• Integument of throat region may be extended by hyoid.
• Fans differ in color, pattern, and size between species
Other behaviors include push-ups and head bobbing.
• Behaviors used in territorial defense, species identification,
and sex recognition.
70
Reproduction
Strategies range from oviparous to viviparous.
• Oviparity is ancestral condition.
• Viviparity has evolved independently multiple times.
• 45 times in “lizards”.
• 35 times in snakes
71
• Benefits of Viviparity
Parent may use thermoregulatory behavior to control
embryo temperature and development.
• May reduce time needed to incubate eggs, especially in
colder climates.
• More common in cold climate species.
72
• Costs of Viviparity
* May reduce reproductive output.
| * Inhibits locomotion of pregnant females.
73
• Effect of Size
• Larger species generally produce more eggs or fetuses
than smaller species.
• Within a species, larger individuals have more offspring
than smaller individuals.
74
• Parthenogenesis
Occurrence of all female species
• Six families of lizard.
• One family of snakes.
Tends to occur in disturbed environments.
• Brings closely related species together contributing to
hybridization.
• Hybridization can lead to parthenogenesis
• Species tend to have higher reproductive potential.
• Capable of repopulating habitat faster after disturbance.
75
Parental Care of Lizards
• Observed in more than 100 species of squamates.
• May be related to thermoregulatory behavior of parent
contributing to development of offspring
76
• Behavioral Control of Body Temperatures
Some species of “lizards” do not thermoregulate.
• Individual body temperatures match environment.
• Ability to adjust exposure, orientation to sun, body
contour, and skin color
• Activity Temperature Range
• Range of temperatures species is active.
• For many “lizards”, activity range is 33-38 °C.
• For snakes, activity range is usually 28-34 °C.
77
Effects that Influence Temperature Regulation of lizards
* Food in digestive system results in thermophilic response.
* Pregnancy.
* Behavioral fever
78
Behavioral Control of Body Temperatures
• Physiological Control
in lizards
• Ability to heat rapidly and cool slowly.
• Peripheral circulation is adjusted to gain heat or reduce
heat loss.
• Postural movements can be used to prevent overheating
79
• Organismal Performance
• Minimizing variation (stabilizing temperature) improves
function.
• Optimal function often matches the activity temperature
range.
80
Lizards must balance thermoregulatory behavior with
| foraging.
Sit-and-wait “lizards” can make small changes in location
and position to regulate body temperature.
• Wide-spread foraging “lizards” may need to stop foraging
to thermoregulate.
81
* Temperature and Ecology
| * Effect of Body Size
• Larger bodied species may forage in shaded habitats
because they cool slowly.
• Larger bodied species may not forage in sunny habitats
because they can overheat.
82
Describe Supercontinent Pangaea
* Extended from pole to pole.
* Regional differentiation due to climate.
* No significant barrier to dispersal.
83
Describe Pangaea Breaks Apart
Laurasia to the north.
• Gondwana to the south.
• Expansion of Tethys Sea
• Formation of Atlantic Ocean.
84
Describe Cretaceous
Continents further separate.
• Northern continents rotate.
• Increase in epicontinental seas.
• Increasing barriers to dispersal.
85
• Changing Climate of Triassic descriptions
Shift from warm and moist to hot and dry.
• Herbivorous vertebrates increased in diversity.
• Archosaurs increased in diversity and became more
prominent.
86
Triassic Flora
* Included gynmosperms, ginkophytes, cycads, and seed ferns.
* Also included ferns, tree ferns, and horsetails.
* Modern descendants not as common.
87
Triassic Herbivorous Fauna
Ranged in size from 10-1000 kg.
• Larger sizes suggest open woodlands.
• Generalists consuming plant material close to the ground.
• Little evidence of arboreal herbivores.
• However, evidence of arboreal insectivores.
88
Late Triassic Events
In Gondwana, shift from seed ferns to gymnosperms.
• Large tetrapods became extinct.
• New vertebrate groups emerge:
• Dinosaurs and mammals.
• Pterosaurs, ichthyosaurs, and plesiosaurs.
89
Triassic Influences on Vertebrate Evolution
Changes in vertebrate posture (more upright).
• Changes in vegetation and habitats
• Low oxygen levels in atmosphere may have favored some
vertebrate clades.
• Increasing diversity and expansion of archosaurs.
• Unidirectional flow in lungs probably advantageous.
• Alveolar lungs may have been at a disadvantage
• Calcareous shell of archosaurs offer greater resistance to
desiccation.
• Advantageous in drying environment of Triassic.
90
• Jurassic Flora
Continues to be dominated by gymnosperms and ferns.
• Reduced diversity of seed ferns.
• High atmospheric CO2 may have supported high plant
productivity.
91
Jurassic Fauna
```
New varieties of insects appear.
• Dinosaurs dominant vertebrate.
• Both large and small herbivores.
• Both large and small carnivores.
• Large Herbivorous Dinosaurs
• Sauropods
• Strongly influenced growth and structure of vegetation.
Appearance of “lizards” and first modern amphibians.
• Evidence of first bird, Archaeopteryx
```
92
Jurassic Influence on Vertebrate Evolution
* High atmospheric CO2.
* Low atmospheric oxygen.
* May have favored archosaurs.
93
• Cretaceous Flora
Similar to Jurassic until late Cretaceous.
• Angiosperms first appear.
• Pollinated by insects.
• Expanded from tropics to more temperate latitudes.
• Predominately low growing plants and small trees.
Greater diversity of insects, especially pollinators.
• First appearance of Hymenoptera
• Snakes and modern crocodilians appear.
• Birds diversify, but do not resemble modern birds.
• Evolution of mammals with complex molars.
• Appearance of three modern lineages:
• Monotremes, marsupials, placentals.
94
Appearance of several new herbivorous vertebrates.
* Hadrosaurs
| * Ceratopsians
95
Observations of Mesozoic Vertebrates
* “Age of Dinosaurs” actually included many vertebrate taxa.
| * All modern tetrapod groups present during Mesozoic.
96
Mesozoic Climates
No polar ice caps existed.
• All terrestrial environments generally frost-free.
• Higher latitudes generally moist.
• Tropical and temperate latitudes dry until late Cretaceous.
• Worldwide cooling began at the end of the Cretaceous.
97
• Significant extinction event at end of Cretaceous.
• Known as K-T boundary.
• Most dinosaurs went extinct.
• Also all marine and flying reptiles.
• Many plants and marine invertebrates went extinct.
Extinction of terrestrial vertebrates and marine
invertebrates at end of Triassic.
• Possible Causes:
• Breakup of Pangaea.
• Bollide impact*.
• Was extinction gradual or sudden?
• Evidence primarily from one continent.
• Dinosaurs fluctuated in numbers throughout Mesozoic
• Evidence of extreme volcanism.
• Increasing evidence of bollide impact at K-T boundary.
• High concentration of iridium.
• Chicxulub crater off Yucatán coast, Mexico.
.
98
• Significant extinction event at end of Cretaceous.
• Consequences of Bollide Impact
• Cloud of dust reducing plant productivity and
contributing to ecosystem collapse.
• Selection against large body size.
• Species greater than 10 kg went extinct.
• Small animals are able to replace losses more rapidly.
