Reptiles

Question 1

Reptiles

Answer 1

• First group of vertebrates to successfully breed on land
• due to the development of the cleidoic (or amniotic) egg
• the embryo within the egg is surrounded by a series of extra-embryonic membranes

Question 2

3 extra-embryonic membranes:

Answer 2

Amnion, Chorion and Allantois

Question 3

Amnion

Answer 3

surrounds the embryo

Question 4

sprawling posture

Answer 4

egs held out to the side of the body, which places limits on their ability to run for long periods.

Question 5

Reptilian organisation

Answer 5

300 million years ago

Question 6

Mesozoic era

Answer 6

225 to 65 million years ago

Question 7

reptilian extinction events

Answer 7

The Permian-Triassic (252 Mya) and Cretaceous-Tertiary (65 mya)

Question 8

The major reptilian groups are recognised by the number of openings in the skull:

Answer 8

the anapsids have none, the synapsids have one, the diapsids have two

Question 9

give birth to live young

Answer 9

viviparity

Question 10

lay eggs

Answer 10

oviparity

Question 11

Pterosaurs

Answer 11

first vertebrates to take to the air

Question 12

Key characteristics of modern reptiles

Answer 12

• cleidoic egg with shell
• skin covered in scales (keratin)
• legs typically in sprawling posture
• ectotherms

Question 13

ectotherms

Answer 13

Gain heat from radiation and conduction,

loose heat by convection or evaporation

Question 14

temperature in reptiles

Answer 14

• Reptiles need less energy than mammal of equivalent size
• Temperature can play a role in sex determination
  (e. g., turtles, cooler nests produce males, warmer nests females)

Question 15

Turtles

Answer 15

• shell fused to ribs and vertebrae
• shoulder blade inside ribcage
• notch on skull where jaw muscles attach

Question 16

Turtle summary

Answer 16

Approx 300 species
Place within the reptile tree is uncertain
Shell (carapace + plastron)
Shoulder blades inside the rib cage
Anapsid skull (no holes)
Several cases of island giants

Question 17

Rhynchocephalia

Answer 17

fossil record

Question 18

Tuatara key facts

Answer 18

• Sole surviving Rhynchocephalia (“living fossil”)
• Most isolated branch on vertebrate tree
• Restricted to islands of coast of New Zealand
• Long-lived (~100 years)
• Rapid rate of molecular evolution

Question 19

komodo dragon

Answer 19

• skull relatively weak
• poorly adapted to generate high bite forces
• rely on causing deep wounds and venom

Question 20

snakes

Answer 20

• evolved from legless lizards

- ancestral snakes possibly burrowed underground

Question 21

Titanoboa

Answer 21

• 12-15m long

- long lived 58-60MYA

Question 22

Lizard vs snake

Answer 22

-around 5800 lizards vs 3400 snakes
-lizards range in size from 29mm to 3m, snakes up to 8.7metres
-

Question 23

Crocodile surfing

Answer 23

• can travel by surinf river and ocean currents
• time travel to coincide with tide turning
• large distances

Question 24

crocodiles and birds

Answer 24

• both are archosaurs

- crocs are closest living relatives of birds