croc lineage

Question 1

what is the order of a croc?

Answer 1

archosaur

Question 2

what are some archosaur characters?

Answer 2

antorbital fenestra and mandibular fenestra

thecodont teeth in sockets

fourth trochanter - for powerful femur-to-tail muscle

Question 3

what causes the croc lineage of archosaurs? what makes them different?

Answer 3

crurotarsal ankle joint at astragalus and calcaneum

astragalus is sutured to the tibia

calcaneum - functionally part of the foot

Question 4

how do crocs walk?

Answer 4

with a high walk - due to an erect gait for overland travel

unlike predecessors who were bipedal

sprawling - more dragging across the floor

Question 5

reasons for erect or sprawling posture?

Answer 5

due to the pelvis and femur

erect - femur has a steeper angle

sprawling - femur is at a shallower angle

Question 6

what are a crocs pelvic aspirations?

Answer 6

inspiration causes the diaphragmatic muscle to pull the liver back

during expiration, - the rectus abdominis muscle will return the pubis to release the diaphragmatic muscle

Question 7

what are the characteristics of the croc scales?

Answer 7

keratinised scales known as scutes cover the skin

has dorsal scutes

also reinforced with bony plates known as osteoderms - known as ridge or keel

Question 8

what causes croc skin colour?

Answer 8

chromatophores:

epidermal melanocytes - stripes and patches and spots on dorsal scales

dermal melanophores - dark and grey background

dermal xanthophores - brown/ yellow or orange

Question 9

what are the integumentary sensory organs?

Answer 9

minute skin elevations on jaws
also body of crocodiles but not alligators

arrays of tactile receptors on epidermis and dermis of integumentary sense organs

detect water movement and movement of prey in jaws