Afrotheria

Question 1

How many orders are contained within this super order ?

Answer 1

6

Question 2

List these 6 orders.

Answer 2

Tenrecs and golden moles
Sengis
Aadvark
Elephants
Hyraxes
Sirena

Question 3

How were these 6 orders grouped into the Afrotheria ?

Answer 3

Molecular analysis
All have a 9 base pair deletion in BRAC1, breast cancer gene
Unlikely to have this deletion via convergent evolution

Question 4

Afrotheria is the oldest clade in the Eutherian tree

True or false ?

Answer 4

True, Evolved 105 million years ago

Question 5

How did the huge diversity of forms occur in this super clade ?

Answer 5

105 Million years ago they were isolated in Africa, had a long period of time to radiate.

Question 6

How many species of tenrec exist ?

Answer 6

Around 34

Question 7

What is important to note about the tenrec ?

Answer 7

The huge diversity within the species
Lesser hedgehog tenrec
Giant otter shrew tenrec

Question 8

Give another example of the incredible diversity of Afrotheria.

Answer 8

Hyraxes and Manatees are very closely related, but are morphologically very different.

Question 9

How many species of elephant exist ?

Answer 9

Around 2, maybe more

Question 10

What is the advantage of the elephants large ears ?

Answer 10

Dissipate heat

Question 11

What makes up a elephant trunk ?

Answer 11

A fused upper lip and nose, used for gathering food

Required due to short neck

Question 12

What are elephant tusks an elongate form of ?

Answer 12

Upper incisors

Question 13

Give the diet of elephants.

Answer 13

They are herbivores, the largest on earth.

Question 14

To support such a great weight what adaption do the elephants have ?

Answer 14

Columnar limbs

Question 15

Describe the social groups of elephants

Answer 15

Live in female groups with offspring.
Will protect them from attack.
Oldest female leads group, Matriarch.
Males ousted at puberty, live alone or in groups

Question 16

What is benefit of the matriarch going through menopause ?

Answer 16

Enables her to invest more care in children and grandchildren

Question 17

Why do elephants protect their children and grandchildren ?

Answer 17

They have similar genes, want to ensure survival of similar genes.

Question 18

Give the closest relation to elephants.

Answer 18

Sengis, elephant shrews

Question 19

Describe the importance of foraging trails to the elephant shrew

Answer 19

Create trails for foraging for invertebrates with long nose

Memorise trails to escape predation, Know short cuts

Question 20

What is the advantage to nipples on the female sengis shoulders ?

Answer 20

Quick getaway to offspring

Easier to reach, require constant feeding

Question 21

How long does it take for sengis to be fully grown ?

Answer 21

A week.

Question 22

Give the organisms contained within the group Sirena

Answer 22

Dugong (1 species)

Manatees (3 species)

Question 23

Give the unusual diet of the Sirena

Answer 23

Feed primarily on plants

process large amounts of low quality plant material daily

Question 24

Describe the digestion system of the Sirena.

Answer 24

Stomachs not compartmentalised
Instead long intestines (45cm)
Large mid gut caecum for cellulose digestion

Question 25

Where is the large mid gut caecum in Sirena found ?

Answer 25

Between the large and small intestines.

Question 26

How do Sirena counteract their low quality diet ?

Answer 26

Minimise energy use;
Move slowly
Live in tropical waters

Question 27

Give the unusual dental adaption of the Sirena.

Answer 27

Constant horizontal replacement of teeth

Can consume abrasive silica

Question 28

How do sirena survive over the winter months when there is no plant matter ?

Answer 28

Store large amounts of fat

Question 29

How can you identify between the 2 species In the Sirena ?

Answer 29

The dugong has a concave tail
Spends all its life in marine
The manatee has a rounded tail.
Spends life in freshwater

Question 30

Give the threats to the Sirena ?

Answer 30

Pollution
Hunting
Boat propellers