Mamma Quiz 3

forelimb diggers

fossorial digger that dig by scratching with forearms and pushing/compacting the soil

Tooth diggers

fossorial - dig with their teeth, while their mouths remain closed

Sand swimmers

Fossorial - use their heads to push up the sand, and their fore and hind limbs to move it, but do not leave a permanent burrow

Traits of a fossorial burrower

• robust/keeled sternum

• greater surface area for muscle attachment on scapula

• enlarged manus/claws

• shorted or flattened humerus

• expanded processes for muscle attachment

• expanded calcaneum

• reinforced zygomatic arch

As a primary form of location, ____ is energetically expensive

burrowing

Gliding

• Patagium acts as airfoil

• Adjust limbs to steer

• energetically cheap - only uses muscles

Challenges of arboreal locomotion

narrow branches

gaps between trees

inclines

balancing

Traits for arboreal

• long and prehensile tails

• long limbs

• claws/gripping pads/opposable digits

• rotating / mobile joints

• low center of mass

Ambulatory

animals who move primarily by walking

Cursorial

animals with adaptations primarily for running

Saltatorial

animals with adaptations primarily for hopping or leaping

Components of locomotion

1. Support

2. Stability

3. propulsion

4. Maneuverability

5. Endurance

Tradeoffs for locomotion

Sacrificing maneuverability for stability

Sacrificing support for speed

Large and heavy species are _____

graviportal

Graviportal

Legs are directly under the body

Bones are columnar

Ankle and knee joints are vertical

Lighter mammals

Limbs slightly outside trunk axis

• crouched limb posture

• rely on muscles for posture and stability over support

Gait

the pattern of regular footfalls during forward movement

Speed

the combined result of stride length and stride rate

_____ is gained by increasing limb reach

stride length

______ is favored by reducing limb so less resistance to “swimming”

Small animals

• shorter strides

• faster pace

• generate/dissipate energy faster

Larger animals

• longer strides

• slower pace/fewer strides

• elastic recoil to store/use energy

Strategies to enhance speed

longer limbs

reduced weight in distal limbs

joints that restrict movement to a single plain

muscle insertions are near the joints they operate

tendons/ligaments act as springs

plantigrade

plantar surface on the ground

Digitigrade

“balls” of feet support the weight “heel” is off the ground

Unguligrade

only the hoof touches the ground

Less of the foot on the ground lengthen bones

lengthens stride

reduction or fusion of tores

increases stride rate

what increases speed

spinal flexion

Carnivores gain speed by exploiting trunk flexibility to extend limb reach and thus stride length

how limbs work - propulsion

legs swing like pendulums under the body

muscles, tendons, ligaments around joints act as levers

Strategies for High speed locomotion and conserving energy by storing it

Allow limbs to move as a pendulum - swinging naturally

Employ ligaments and tendons as springs

Saltatorial locomotion - hopping

lengthen one or more segments of the hind limb

posterior shift of body mass

enlargement of the hip muscles and elongation of the tendons

large hind feet for take off/landing

long tail for balance

Positives for being a carnivore

energy rich

easy to digest

negatives for being a carnivore

scarce

locate, capture, kill

larger carnivores

small prey is not worth the energy expended

prey = or > predator

smaller carnivores

Prey < predator

Order Carnivora characteristics

elongate/conical canines

carnassials

teeth are diphyodont

hunting strategies = solitary, paired or in small groups - stealth and ambush, stalk and run, prolonged chase

pelage = camouflage

Turbinal bones - large, complex

Anal sacs with scent glands

Hypercarnivory

• reduced molars and reduced non-carnassial Pm’s (= reduced grinding)

• enlarged carnassials and canines

• short rostrum

• meat only diet

• promoted by larger body

Hypocarnivory

• unreduced or enlarged molars

• reduced carnassials

• longer rostrum

• omnivorous diet

Skull characteristics of Carnivora

sagittal crest conspicuous

zygomatic arch robust

large temporalis

large coronoid process

expanded brain case

jaw articulation at tooth row = more crushing force

C shaped mandibular fossa = jaw does not dislocate as prey struggles to get free

Carnivora digit characteristics

claws on all digits

wrist = fused centrale, scaphoid, lunar

clavicle (reduced/absent) - greater flexion

femur lacks third trochanter

Olfactory communication carnivora

Turbinal bones - can comprise 1/3 of the skull, less expansive in omnivorous carnivorans, increase surface area for detection of chemical cues

information conveyed = identity, physical condition, time since deposited, defensive secretions

Why scent mark?

Territoriality

navigation

mediate interactions

deter predators

Its important for many mammals who are nocturnal, secretive, and solitary

Carnivora reproduction

baculum

induced ovulation

mating systems - diverse

sexual dimorphism

altricial/precocial young

Pleistocene carnivores were

more numerous; high diversity of coexisting large predators

great proportion were hypercarnivores

larger in size than those today

Two suborders of carnivora

Feliformia “catlike”

Caniformia “doglike”

Feliformia: Felidae

Family: Cats

nearly worldwide

diverse habitats

strict carnivores

“super” predators

hunt mostly at night, ambush or stalk, kill prey by suffocating or biting neck, solitary (all but lions)

Characteristics of Felidae

Large front facing orbits - binocular vision

shorted rostrum - increases bite force

loss/reduction teeth

large, conical canines

well developed carnassials

digitigrade - curved, sharp claws, retractable

eye shine

Tapetum lucidum, a special reflective layer beneath the retina

enhances night vision or seeing in dim light

• non absorbed light bounces back “shines”

Nandiniidae

african palm civet

Felidae

cats

Viverridae

civets and genets

Hyaenidae

aardwolf and hyenas

Herpestidae

mongooses

Eupleridae

Malagasy mongooses

Carnidae

dogs

Ursidae

bears

Ailuridae

the red panda

Mephitidae

skunks

Procyonidae

raccoons

Mustelidae

weasels, badgers, otters, wolverines

Pinnipedia

walrus, seals, sea lions

Canidae characteristics

more omnivorous than many carnivorans

adapted for endurance more than for speed

chases, exhaust prey

neck grab and shake, death from shock

senses: smell is acute, sight is less well developed than in cats

Canidae characteristics skull

elongate rostrum

many teeth

molars bunodont

well developed carnassials

long canines

non retractible claws

reduced digits, digitigrade, long limbs

Pinnipedia

adaptations to terrestrial and aquatic environments

not as well adapted for aquatic as cetaceans/sirens

most vulnerable and slow on land

aquatic adaptations: fusiform, pinnae reduced, testes abdominal, nostrils valcular, eye covering, pelage thick, blubber

terrestrial adaptations: shortened limbs, reduced agility, “wrigglers”

nearsighted

Phocidae

True seals

hind limbs propel

large lumbar vertebrae

lurch forward, weight on abdomen/pelvis

Odobenids and Otarrids

Forelimbs propel

enlarged cervical and thoracic vertebrae

enlarged scapula

hind limbs can rotate forward when on land

“walkers”, hind limbs rotate and bear weight, forelimbs provide balance

Pinnipedia skull and dentition

generalized feeders

homodont cheek teeth

teeth grasp/hold prey, don’t chew

narrow skull

hear well underwater

Order Pholidota

Pangolins “scaly one”

scaly anteaters

forest, woodland, savannah

insectivores

keratinized scales

Characteristics of Pholidota

Keratinized scales

complex turbinals

reduced auditory bullae

ZA incomplete

slender mandible

edentate

long powerful tongue

protrusible tongue, extensive salivary glands, thick stomach, thick skin, massive claws, plantigrade, long tail, scent mark

Ungulates

hoofed mammals

Perissodactyla and Cetartiodactyla

larged bodied mammals

herbivorous

rapid cursorial locomotion

Ungulate hind limb morphology

Modified ankle bone

limits movement to a single plane

greater flexion and extension

Perissodactyls

Mesaxonic : passes through enlarged 3rd digit

“odd toed ungulates”

Artiodactyls

Paraxonic: passes between 3rd and 4th digit

“even toed ungulates”

Perissodactyla characteristics

Unguligrade

“odd toed” - loss of digits 1 and 5

herbivores - elongate rostrum, hypsodont, brachydont, lophodont, hindgut fermenter

reproduction: long lived, long gestation,

Perissodactyla: Tapiridae

Most primitive of extant Perissodactyla

moist tropical forests

4 toes on forefeet

short proboscis

solitary and nocturnal, strong swimmers

Perissodactyla: Rhinocerotidae

browsers and grazers

high occipital crest

horns - supported by nasals, keratin

solitary, territorial, require permanent water

Perissodactyla: Equidae

Horses, zebras, asses

Long, slender limbs

3rd digit only

fused radius and ulna

neck mane and forelock

elongate rostrum

hypsodont teeth

lack canines

diastema

Behavior: social, polygynous herds, led by stallion

Evolution of horses

small, forest dwelling browser —→ large, open land, grazer

• increase in body size and lengthening of limbs

• reduction in number of digits

• lengthening of rostrum

• increase in size and complexity of cheekteeth

“many eyes hypothesis”

the evolutionary trend captured in horses is evident today among many forest vs. grassland groups of species

• reflects collective animal behavior

• forest species are solitary

• grassland species are social, they herd

• strong selective pressures against predators

Forest “many eyes hypothesis”

Browser

small, short neck

shorter rostrum

eyes more forward

solitary

antipredator: camoufalge, freeze, zig zag run

Grassland “Many eyes hypothesis”

Grazer

larger in size, longer neck

longer rostrum

eyes apart, on both sides

social herding behavior

Anti predator: herding/aggregation, run fast in a straight line

“Artiodactyla” three suborders

• suiformes = pigs and warthogs, peccaries, hippos

• Tylopoda = camels, llama, vicuna

• Ruminantia = mouse deer, deer, giraffe, musk deer

Suborder Suiformes

Pig and warthogs, peccaries, hippos

• forest, brush, savannah

• bunodont molars

• canines are tusklile

• four tours

• stomach

Suborder Tylopoda

Camels, llamas, vicuna

arid and semi arid regions

digitigrade

Y shaped cannon bone

canines present, incisor canine like

ruminant

Suborder Ruminantia

Giraffers, deer, antelope, sheep, goats, cattle

strict herbivory and cursorial locomotion

ruminants

selenodont molars

missing upper incisors

canines reduced/absent

often have antlers/horns

Antlers

grows from frontal bones, regulated by testosterone

while growing, covered in skin/soft hair which feeds growing bone

when bone is fully ossified - the skin dies/velvet shed

antlers shed after mating period

cycle regulated by photoperiod

used for male male competition

Horns

occur in the family Bovidae

extension of the frontal bone

keratinized sheath

permanent

grows through adult life

all wide males, some females

Mouth

masitication, saliva

esophogus

transport tube

stomach

initial digestion, some physical processing