Flashcards in Afrotheria Deck (30)
How many orders are contained within this super order ?
List these 6 orders.
Tenrecs and golden moles
How were these 6 orders grouped into the Afrotheria ?
All have a 9 base pair deletion in BRAC1, breast cancer gene
Unlikely to have this deletion via convergent evolution
Afrotheria is the oldest clade in the Eutherian tree
True or false ?
True, Evolved 105 million years ago
How did the huge diversity of forms occur in this super clade ?
105 Million years ago they were isolated in Africa, had a long period of time to radiate.
How many species of tenrec exist ?
What is important to note about the tenrec ?
The huge diversity within the species
Lesser hedgehog tenrec
Giant otter shrew tenrec
Give another example of the incredible diversity of Afrotheria.
Hyraxes and Manatees are very closely related, but are morphologically very different.
How many species of elephant exist ?
Around 2, maybe more
What is the advantage of the elephants large ears ?
What makes up a elephant trunk ?
A fused upper lip and nose, used for gathering food
Required due to short neck
What are elephant tusks an elongate form of ?
Give the diet of elephants.
They are herbivores, the largest on earth.
To support such a great weight what adaption do the elephants have ?
Describe the social groups of elephants
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
What is benefit of the matriarch going through menopause ?
Enables her to invest more care in children and grandchildren
Why do elephants protect their children and grandchildren ?
They have similar genes, want to ensure survival of similar genes.
Give the closest relation to elephants.
Sengis, elephant shrews
Describe the importance of foraging trails to the elephant shrew
Create trails for foraging for invertebrates with long nose
Memorise trails to escape predation, Know short cuts
What is the advantage to nipples on the female sengis shoulders ?
Quick getaway to offspring
Easier to reach, require constant feeding
How long does it take for sengis to be fully grown ?
Give the organisms contained within the group Sirena
Dugong (1 species)
Manatees (3 species)
Give the unusual diet of the Sirena
Feed primarily on plants
process large amounts of low quality plant material daily
Describe the digestion system of the Sirena.
Stomachs not compartmentalised
Instead long intestines (45cm)
Large mid gut caecum for cellulose digestion
Where is the large mid gut caecum in Sirena found ?
Between the large and small intestines.
How do Sirena counteract their low quality diet ?
Minimise energy use;
Live in tropical waters
Give the unusual dental adaption of the Sirena.
Constant horizontal replacement of teeth
(Can consume abrasive silica)
How do sirena survive over the winter months when there is no plant matter ?
Store large amounts of fat
How can you identify between the 2 species In the Sirena ?
The dugong has a concave tail
Spends all its life in marine
The manatee has a rounded tail.
Spends life in freshwater