Lecture 14 Flashcards
What is the stance Plantigrade and give examples of animals with this type of stance?
Feet on the ground, with flexion at wrist/ ankle
E.g. Lipotyphla, Ursidae (Carnivora), Rodentia
What is the stance Digitigrade- explain? Give examples of animals that have this stance
Metatarsus/ carpi off the ground
Creates another extension element in the limb: more power/ acceleration
E.g. fix and Lagomorph hindlimbs
What is the stance Unguligrade?/ explain/ describe this type of stance.
Terminal phalanges (digits) and hooves support weight; heavy proximal and little distal musculature; extremities moves via tendons; great speed and endurance possible
What are the two hypotheses as to why cursorial herbivores evolved? Which hypothesis does the evidence support?
H1: an evolutionary arms race between predators and prey
H2: low productivity grasslands replaces high productivity woodlands, requiring wider ranging to obtain food
Circumstantial evidence supports H2 rather than H1
What are elephants massive columnar limb bones called? What are they for?
Graviportal
Resist crushing under great body weight (cf. large herbivorous dinosaurs e.g. Diplodocus)
What are the adaptions of fossorial?
Short, massive limbs, specialised claws and teeth
What are the adaptions of Arboreal?
. Gripping feet and claws
. Tail for balance
. Opposable thumbs; prehensile (gripping) tail in primates
What is the adaption of Volant forms?
Patagium (flight membrane)
What is the adaptions of Chiroptera? Give examples of these animals
Powered flight, patagium (flight membrane) stretched over phalanges of forelimb to hindlimb and to tail (uropatagium); ultrasonic Austen for orientation and prey capture (Greater horseshoe bat, Seychelles fruit bat)
What are the adaptions of Amphibious forms?
Tail as propeller and rudder, webbed feet, paraxial swimming
What is the sub-order that shows Axial swimming?
Pinnipedia
What family are walrus in?
Odobenidae
What family are eared seals in? Give examples of eared seals
Otaridae
Sea lions, fur seals
What family for true seals and elephant seals in?
Phocidae
Describe how eared seals (Otaridae) move on land
Substantial forelimb props; hindlimb rotates forward on land
What families are in the sub-order Pinnipedia?
. Odobenidae (Walrus)
. Otaridae (Eared seals)
. Phocidae
Describe how Phocidae (true seals, elephant seals) swim
Forelimbs reduced, hindlimbs permanently reflected backwards (Northern elephant seal, Atlantic grey seal)
Give the group that are ‘mainly aquatic forms’
Sub-order Pinnipedia (axial swimming)
Give the order of aquatic forms that are completely aquatic and the two sub-orders it is divided into and examples of the species in these sub-orders
Cetacea
- Odontoceti (toothed whales): sperm, killer, dolphins, porpoises
- Mysticeti (Baleen whales); blue, right, minke
Describe Sirenia: examples of Sirenia, what they are classified into on molecular grounds (mtDNA sequence comparison), where they are distributed
. Dugong, manatee (4 species)
. Classified into Afrotheria with elephants, aardvark, hyrax on molecular grounds
. Distribution now marine and estuarine tropics
What is the largest order of mammal species?
Rodentia
What do people use phylogenetic trees for?
To piece together how related the different species are
Describe how animals are grouped together using morphological cladistics, why have things been moved around?
Based on morphological characters- so things that look similar and perhaps things that eat similar things and have similar traits have been put together, so mainly based on form and function but as understanding through molecular technology (genetic makeup- mRNA) (molecular cladistics) has increased things have moved around in their trees
Give two examples of an animal that was moved around in a evolutionary tree based on its molecular cladistics compared to its morphological cladistics (give the Latin name)
Dasypus novemcinctus (9-Banded Armadillo) Echinosorex gymnure (moon rat)
How do Paenungulates (elephant, hyrax, Sirenia) move around based on the different cladograms generated by morphological and molecular cladistics?
They are close to ungulates on morphology, but a separate stem group on molecular evidence, including hyrax and sirenians
How have Lipotyphla (insectivores excluding morphologically similar African forms: tenrec, golden mole) move around based on the different cladograms generated by morphological and molecular cladistics?
Moved to being a clade in their own from being more related to bats and ungulates (when looking at a molecular evidence they move and become a clade if their own)
What are bats close to on morphology, on molecular evidence?
. Close to ungulates on molecular evidence
. Close to primates on morphology
Give an example of a few animals which emerge as close relatives on both cladograms generate by morphological and molecular evidence
Tree shrews, flying lemurs and primates
There is lots of debate and changes in naming because we are still defining what is a species and what is a sub-species. What is this important in?
Conservation
Give examples of species that have been reclassified
. Tursiops Australis: mouse we found to be an additional species of mouse
. Mud cypriacus: Dolphin was found to be an additional species of dolphin
Explain the importance of red-list and Giraffe (Giraffa Camelopardalis)
These giraffes haven’t bred in millions of years. The red-list that look after red-listed animals still only class one species of giraffe, they don’t think there is enough evidence to classify 4 species of giraffe
Give the Latin name of Giraffes
Giraffa camelopardalis
What two phenomena have affected mammalian distribution? Include examples
. Vicariance- earth history (geology)- continental drift e.g. monotremes in New Guinea and Australia
. Dispersal movements- can control their movements and definition of what their range is- leads to some species being present in some areas and not others e.g. marsupials in Australia
Give examples of cursorial herbivores
. Perissodactyla (Neartic) (horses)
. Artiodactyla (Palaearctic) (rhinos)
. Extinct Litopterna (Neotropical)
. Marsupial Macropodidae (Australian Kangroks, Walabees)
What are cursorial herbivores?
Wide ranging and can run
Give some examples of large carnivores
. Wolf (holartic)
. Extinct marsupial Borhyaenidae (Neotropical)
. Marsupial Thylacinus (Australian)
What list are threatened mammals on?
They are red-listed
Where is the largest area we are seeing threatened species? (Highest density of threatened species)
. South-east Asian
. Thailand
. Vietnam
. Some across the Amazon as well
Why are a lot of species in Madagascar threatened?
Because of their small ranges
