What is an insectivora?

1. What is an insectivora?

2. Insectivora Macroscelidea (elephant shrew), Scandentia,(tree shrew) Dermoptera (flying lemurs) Primitive group: 130 mya

3. Does size matter? Insectivores • Insectivores are considered to be "primitive" mammals • Smooth brain:_not as intelligent??? • Insectivores are named after their tendency to eat insects or invertebrates

4. Erinaceidae: hedgehogs Tenrecidae: tenrecs and otter shrews. Soricidae: shrews Chrysochloridae: golden moles. Solenodontidae: solenodons. Talpidae: moles and desmans. Insectivora: Reference Page There are 419 species in 6 families:

5. 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.

6. Teeth are rooted, so do not grow throughout life. Anatomy defines species. Ex. some species are open rooted teeth, grow throughout life

7. Insectivora’s are not Rodents: Why:_____________________

8. Insectivora: Fossil History Earliest insectivores date to the mid-Cretaceous (100MYA) Recognizable soricids and talpids date to the Eocene (50MYA). No Big Changes from ancient to now: Why? ____________________________________

9. 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.

11. 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.

12. Erinaceidae • Hedgehogs also rub saliva over their spines. Interestingly, there are reports of hedgehogs killing toads, to produce ‘venemous spines.’

13. 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

14. Extreme modification of the pectoral girdle - including rotation of the fore-feet.

15. 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

16. Tenrecidae • Tenrecs are found in Madagascar only (this is bad news). Otter shrews found in west-central Africa.

17. 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!

18. Chrysochloridae: Golden Moles • Found in central and southern Africa. • They have iridescent fur. • Vestigal eyes.

19. Chrysochloridae: Golden Moles • They push soil w/ the snout, then push soil under the body with the limbs. • Claw on 3rd digit is enlarged.

20. 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.

22. Solenodontidae • Submaxillary glands produce toxic saliva, which flows into the bite via grooved 2nd incisor.

23. Soricidae: Shrews • 23 genera and 312 species. • Generally small (3g - 100g). • Organized into 2 subfamilies: ‘red-toothed’ shrews and the ‘white-toothed’ shrews.

24. 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.

25. 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.

26. 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.

27. Elephant shrew video

28. Scandentia: Tree Shrews • Have long been considered primates..

29. 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.

30. Dermoptera • These are the ‘flying lemurs’ or Colugos. • In the past, they have been classified with bats, primates, and insectivores.

31. Dermoptera • They weigh up to 2kg, and can glide at up to 25m/s which is very fast for a glider.

32. Use your notes to identify the following groups Only one from each group: (use your reference page) 4.________ • 1. ______ • 2.______ • 3. _______ • (hint not an elephant shrew) 5. ________ 6.________

33. Work in groups of two: • A. List 5 unique characteristics of insectivora • B. List 5 similarities that insectivora share with other mammals. • C. List 5 examples of insectivora • D. Explain in 2-3 sentences, why it is believed that insectivora animals are “primitive” Do you think they are primitive?