What is an insectivora?. Insectivora Macroscelidea (elephant shrew), Scandentia,(tree shrew)...
-
Upload
joshua-woods -
Category
Documents
-
view
221 -
download
0
Transcript of What is an insectivora?. Insectivora Macroscelidea (elephant shrew), Scandentia,(tree shrew)...
Insectivora
Macroscelidea (elephant shrew), Scandentia,(tree shrew) Dermoptera (flying lemurs)
Primitive group:
130 mya
Insectivores Insectivores are
considered to be "primitive" mammals
Smooth brain:_not as intelligent???
Insectivores are named after their tendency to eat insects or invertebrates
Does size matter?
Insectivora: Reference Page
Erinaceidae: hedgehogs
Tenrecidae: tenrecs and otter shrews.
Soricidae: shrews
Chrysochloridae: golden moles.
Solenodontidae: solenodons.
Talpidae: moles and desmans.
There are 419 species in 6 families:
Insectivora: Morphology Generally small. Rostrum (snout) tends to
be long. Fur often consists only of
guard hair (modified in some forms as spines).
Small braincase excellent sense of smell
and touch, but have poor senses of sight and hearing.
Teeth are rooted, so do not grow throughout life. Anatomy defines species. Ex. some species are open rooted teeth, grow throughout life
Insectivora: Fossil HistoryEarliest insectivores date to the
mid-Cretaceous (100MYA)
Recognizable soricids and talpids date to the Eocene (50MYA).
No Big Changes from ancient to now: Why?____________________________________
Erinaceidae
7 genera and 21 species. Hedgehogs have barbless spines. Hedgehogs are nocturnal and mainly
terrestrial, or semi-arboreal. They are omnivorous - invertebrates, eggs,
fruit, carrion.
Erinaceidae Spines in hedgehogs
are soft at birth, and harden a few weeks after birth.
In a defensive posture, the animal rolls up in a ball, using a band of muscles.
Erinaceidae Hedgehogs also rub saliva over their
spines. Interestingly, there are reports of hedgehogs killing toads, to produce ‘venemous spines.’
Talpidae: Moles 17 genera and 42 species, distributed
throughout Europe, Asia, Japan, and North America.
http://www.youtube.com/watch?v=4rAk4pE0Vuw&safety_mode=true&persist_safety_mode=1
Talpidae: Desmans– Eat aquatic invertebrates and fish– Some species have long, laterally
compressed tails.– Some evidence that they use echolocation to
locate prey.– http://www.arkive.org/russian-desman/
desmana-moschata/video-05.html
Tenrecidae Tenrecs are found in Madagascar only
(this is bad news). Otter shrews found in west-central Africa.
Tenrecidae Otter shrews (not surprisingly) look a lot
like otters and are actually quite large. Some Tenrecs can hibernate, and most
have relatively low body temperatures. The common Tenrec has as many as
32 offspring in a single litter!
Chrysochloridae: Golden Moles Found in central and southern Africa. They have iridescent fur. Vestigal eyes.
Chrysochloridae: Golden Moles They push soil w/ the snout, then push
soil under the body with the limbs. Claw on 3rd digit is enlarged.
Solenodontidae 2 species. 1 restricted to Cuba, the
other to Haiti and the Dominican Republic (this is not good news).Why?___________________ _____________________________
Look like a cross between a rat and a shrew.
Omnivorous.
Solenodontidae
Submaxillary glands produce toxic saliva, which flows into the bite via grooved 2nd incisor.
Soricidae: Shrews 23 genera and 312 species. Generally small (3g - 100g). Organized into 2 subfamilies: ‘red-toothed’
shrews and the ‘white-toothed’ shrews.
Soricidae Smallest shrews are
pygmy shrew while largest is House Shrew
Most have short legs. 2 forms have webbed
feet. Small eyes, pointed
rostrum, short dark fur.
Soricidae Some use high frequency sound for
communication, orientation, and prey detection. (Like bats)
Short lived: one year. Often associated w/ moist habitats. Some Shrews are poisonous.
Macroscelidae: Elephant shrews (not a real shrew) 4 genera and 15 species
of elephant shrews. Central and eastern
Africa. Insectivores to
omnivores. Can move bipedally. Long, flexible snout,
large eyes and long ears.
Scandentia: Tupaiidae Restricted to Asia. Mostly diurnal and omnivorous. Not all are arboreal, and they are not
shrews. Most scent mark. Resemble squirrels in general
morphology.
Dermoptera These are the ‘flying lemurs’ or Colugos. In the past, they have been classified
with bats, primates, and insectivores.
Use your notes to identify the following groups Only one from each group: (use your reference page) 1. ______
2.______
3. _______
(hint not an elephant shrew)
4.________
5. ________
6.________