Observable features in the head of the Agama lizard
- Terminal mouth
- Wide mouth
- A pair of nostrils
- Bulged/protruding eyes
- Upper and lower eyelids
- Nictitating membranes
- A pair of Oval eardrums
- A ridge of scales protects the eyes
- Short neck
- Nuchal crest (crest of skin) above the neck
- Gular fold (fold of skin) below the chin
LATERAL VIEW OF THE HEAD
State the sex of specimen
The specimen shows sexual dimorphism; the male is different from the female.
Differences between the male lizard and the female lizard.
| MALE LIZARD |
FEMALE LIZARD |
| Relatively larger in size |
Relatively smaller in size. |
| Brightly coloured |
Dull coloured |
| Bright orange head |
Light brown or yellow head |
| Nuchal crest prominent |
The nuchal crest is less prominent |
| Gular fold prominent |
Gular fold less prominent |
| Hemi-penis present |
Hemi-penis absent |
| Pre-anal pad around cloaca |
Pre-anal pad absent |
| The tail is blue at the base |
The tail is usually light brown |
What role is played by the specimen in its colony?
- Defends the colony
- Mates and fertilises all females
What are the functions of scales in the specimens?
- Protection against mechanical injury
- Protection against desiccation
- provides camouflage against predation
Similarities between the heads of the toad/frog and the lizard
- Triangular shape
- Wide mouth
- Nostril above the mouth
- Protruding eyes
- The tympanum or eardrum is slightly below the eye.
Differences between a lizard and a cockroach.
| LIZARD |
COCKROACH |
| Wing absent |
Wings present |
| Two pairs of legs |
Three pairs of legs |
| Tail present |
Tail absent |
| Possess antennae |
Antennae absent |
| Possess simple eyes |
Possess compound eyes |
| Large in size |
Smaller in size |
| Possess teeth |
Teeth absent |
Similarities between a lizard and a cockroach
- Presence of legs
- Presence of eyes
- Claws in limbs
- Scales and plates covering the body
Similarities between a lizard and Tilapia
- Backwardly overlapping scales
- Tail
- Eyes
- Nostril
- Cloaca
- Terminal mouth
Differences Between Agama Lizard and Tilapia
| TILAPIA |
AGAMA LIZARD |
| Scales are removable |
Scales are not removable. |
| Lidless eyes |
Eyes with eyelids |
| Possess fins |
Fins absent |
| Legs absent |
Legs present |
| Operculum present |
Operculum absent |
| Possesses gills for gaseous exchange |
Possess lungs for gaseous exchange |
| The tail is short |
Tail is long |
| Possess a lateral line |
Lateral line absent |
| Absence of tympanum |
Presence of tympanum |
| Absence of gular fold |
Presence of the gular fold |
| Absence of nuchal crest |
Presence of nuchal crest |
