Final Flashcards
Four aspects of life that mammals need energy and nutrients to maintain
- Growth
- Activity
- Reproduction
- Survival
Describe the digestive tract of insectivores
- Ingest minimal fibre so alimentary canal is short
- Typically lack a cecum
Describe the digestive tract of carnivores
- Short intestine and colon
- Small or no cecum (may be replaced by appendix)
Describe the digestive tract of non-ruminant herbivores
- Simple stomach, large cecum
Describe the digestive tract of ruminant herbivores
- Four-chambered stomach
- Large rumen
- Long small and large intestine
Which nerve, that coordinates swallowing and respiration, is designed imperfectly?
- The laryngeal nerve (a branch of the vagus nerve)
What is a guild?
- A group of species having similar ecological resource requirements and foraging strategies, and therefore having similar roles in community
Based on what characteristics can echolocating bats be divided into guilds?
- Preferred habitat
- Foraging behaviour
- Distinct adaptations to wing morphology
- Structure of echolocation signals
Difference between fundamental and realized niche?
- Fundamental = Niche that is free from interference
- Realized = Niche that is narrower and involves interactions with other species
What does myrmecophagous mean? What traits to these mammals typically have?
- Myrmecophagous: Feeding primarily on colonial insects such as ants and termites
- Characteristics: Reduction of teeth (or teeth peg-like if present), long and extendible tongues, elongated snouts, strong front feet, large claws, and enlarged salivary glands
Describe tusks in walrus and their functions
- Tusks are enlarged canines that lack enamel
- Used in aggressive encounters, establishing dominance hierarchies, feeding, locomotion, breaking through ice
Difference between dugong and manatee diet?
- Dugongs eat aquatic vegetation that is much softer than that consumed by manatees
- Have more peg-like dentition than manatees
- Manatees eat water hyacinth, mangrove leaves, etc.
What is the Eimer’s organ?
- Sensitive tactile organ on the snout of moles and desmans
What can the cortex in the brain tell you about the importance of different body parts in mammals?
- The amount of brain cortex devoted to processing information from a certain body part can reflect its importance for the animal
What pairs of teeth are for crushing bones in the bone crushing wolf and spotted hyaena? What does this free up for cutting meat?
- Bone crushing wolf (extinct) = P4/P4
- Spotted hyaena = P3/P3 (access fat in long bones)
- Frees up carnassial pair (P4/M1) for carnassial and cutting meat
What do differences in mandibular force profiles reflect in mammals?
- Differences in feeding behaviour
- Solitary predators (felids) deliver powerful canine killing bites, and have strong canine bite region
- Social (pack) hunters (canids and hyaenids) deliver shallow bites, and display a weaker canine bite
How could you reconstruct a paleo-ecosystem?
- Body mass - prey size relationship
- Morphology and bite patterns
- Tooth wear patterns (microwear and breakage)
What is cryptic speciation?
- Genetics revealing divergence from a long time prior, making two separate species
- Seen in clouded leopards
How do jaw muscles differ in herbivores and carnivores?
- Carnivores have well-developed temporalis muscle for seizing and holding prey
- Herbivores have a large masseter muscle for grinding
What are the adaptations seen in sanguinivorous bats?
- Modified rostrum with large incisors and canines
- Small cheek teeth
- Tongue with grooves at border (work like straws)
- Stomach is long and tubular, highly distendible
- Small intestine is thin
- Kidneys modified to quickly process water
What are the two compounds in the venom of vampire bats?
- DSPA and Draculin
What organs in the nose of bats are sensitive to infrared radiation?
- Pit organs
What are callosities?
- Whale lice and barnacles that grow on some species
What are the two main groups of herbivores?
- Broswers and grazers; Gnawers
- Browsers: Feed primarily on stems, twigs, buds, and leaves
- Grazers: Feed primarily on grasses and forbs
- Gnawers (rodents and lagomorphs)
Define the following terms:
- Graminivore
- Gumivore
- Folivore
- Frugivore
- Granivore
- Nectarivore
- Graminivore = grasses
- Gumivore = exudates of trees (saps, resins, gums)
- Folivore = leaves
- Frugivore = fruit
- Granivore = seeds
- Nectarivore = nectar
How do upper incisors differ in ruminant vs. non-ruminant herbivores?
- Ruminant herbivores have lost their upper incisors and their lower incisors bite against a callous pad on the upper gum
What is the reproductive period of male African elephants called?
- Musth
What can be a source of mortality in older elephants?
- Molar wear - inefficient food processing
What are the four compartments of ruminant’s stomach? What function do they serve?
- Rumen (largest chamber where food is moistened, kneaded, and mixed with microorganisms)
- Reticulum (area where “cud” is formed and can be regurgitated, allowing animal to re-chew material)
- Omasum (further kneading occurs)
- Abomasum (fourth and final chamber, true stomach, digestive enzymes are secreted and escaping microorganisms are killed)
Difference between foregut and hindgut fermentation?
- Foregut fermentation is more efficient because microorganisms digestion starts sooner and foregut can digest some of the microorganisms
- Hindgut fermenters do not digest microorganisms
- Hindgut fermenters are efficient if food is high in protein and if forage is dominated by indigestible material
Difference between cercopithecine and colobine monkeys?
- Cercopithecine = have cheek pouches
- Colobines = lack cheek pouches, have sacculated stomachs (evolved for leaf diet), large salivary glands, most folivores
What is the metabolic rate so low in sloths?
- In arboreal folivores, muscle mass makes up only small proportion of body which therefore has larger proportion of tissue with low metabolic rate
- Leaves have low caloric density. Since maximal daily bulk that can be processed is limited, energy available from leaves is low - constraint on growth
- Number of toxic substances, including alkaloids, terpenes, and phenols, are present in leaves. Low BMR in leaf-eating mammals may reduce the absorption of these substances (limit may be on how fast liver can detoxify compounds)
Which bone is the “false thumb” in giant pandas and red pandas?
- Radial sesamoid (carpal bone)
What is mycophagy?
- Fungus eating species
What are the constraints on bears consuming wild fruits for fall energy?
- Intake rate
- Physiological capacity of GI tract
- Metabolic efficiency of gain in body mass
- Foraging efficiencies constrain growth rates
Marginal value theorem predicts that individuals will stay longer in what situations?
- Profitable patch
- As distance between patches increases
- When environment as a whole is less profitable
What are the two different types of caches?
- Scatter hoarding = Different locations, need spatial memory
- Larder hoarding = Bring back to one spot only
What are infrasound and ultrasound?
- Infrasound = < 20 Hz
- Ultrasound = > 20,000 Hz
What are some of the documented, short-term responses of cetaceans to human-produced sound?
- Longer dive times
- Shorter surface intervals
- Evasive movements away from source of sound
- Attempts to shield young
- Increase in swimming speed
- Changes in song note durations
- Leave area
What organ in sperm whales may act to modify buoyancy or as a lens to focus outgoing sound waves?
What structure in the forehead of all whales serves as acoustic lens for echolocation sound production?
How do cetaceans generate clicks?
- Spermaceti organ
- Cetacean melon
- Via structure just below blowhole called “monkey’s lips” that smack together
What can bats detect through echolocation?
- Distance and speed (return frequency)
- Size (subtended angle)
- Time delay and amplitude give azimuth (location)
- Inference patterns with inner ear surface gives elevation
Difference between constant frequency signals and frequency modulation signals?
- Constant frequency signals = Constant frequency have significant time duration; good for detecting presence, and through Doppler shift, whether prey is approaching or departing
- Frequency modulation signals = Short duration, but sweep broad frequency range; ideally suited to determine size, shape, surface qualities, range of target (shifts in frequency to get needed information)
Difference between ethmoturbinates and maxilloturbinates?
- Ethmoturbinates = Olfaction
- Maxilloturbinates = Respiration (heat and water conservation)
What is mosaic evolution?
- Pattern wherein the different compounds of an existing structure evolved at different rates
What two glands play a major role in controlling the endocrine system?
- Hypothalamus
- Pituitary gland
- Hypothalamus controls pituitary, and pituitary controls release of hormones
What are endocrine glands?
- Specialized groups of cells that produce chemical substances called hormones that act as messengers to cells throughout body (main components = pituitary, pancreas, ovaries, testes, thyroid, adrenals)
Follicle stimulating hormone (FSH)
- Produced by anterior pituitary
- Stimulates ovarian follicles and estrogen secretion in females
- Stimulates spermatogenesis in males and testosterone secretion
LH
- Produced by anterior pituitary
- Stimulates corpus luteum development and production of progesterone in females
Estrogen
- Any of the C18 steroir hormones that generate estrus in females
- Produced by developing follicles (stimulated by FSH)
Progesterone
- Steroid hormone produced in follicle and corpus luteum
- Promotes growth of uterine lining (allows egg implantation)
Oxytocin
- Produced in anterior pituitary
- Causes rhythmical contractions of uterus during parturition
- Enhances milk “letdown”
Prolactin
- Produced in anterior pituitary
- Reproduction and water balance
- Promotes corpus luteum in ovaries
- Promotes milk production
Testosterone
- Steroid hormone secreted by testes
- Responsible for development and maintenance of sexual characteristics and sperm production
What is cytochrome P450?
- Enzymes
- Body’s mechanism to dispose of potentially harmful substances by making them more water-soluble
- Vital to formation of cholesterol and steroids
- Abundant in liver
What is the function of the thyroid gland?
- Regulates metabolic activities by hormone thyroxin (thyroid gland is regulated by anterior pituitary)
- Regulates cellular respiration
- Cold adapted individuals have higher thyroid output than those not exposed to cold
What are the five types of WBCs?
- Neutrophils (consume foreign particles, primarily bacteria and fungi)
- Lymphocytes (produce antibodies - IgA (mucosal), IgD (lymphocyte cell membrane), IgE (only in mammals - allergies and parasites), IgG (most abundant in serum), and IgM (first AB present in infants)
- Monocytes (convert to macrophages and consume bacteria and viruses)
- Eosinophils (destroy and consume antigen-antibody complexes)
- Basophils (congregate at tissues with inflammation or infection and release histamines)
What are the four lines of defense in mammals?
- Skin and lining of digestive system, respiratory system (mechanical)
- Inflammatory reaction (swelling, WBCs accumulate)
- Proteins activated at wound sites
- Immune reactions (immunoglobulins, ABs)
Describe the immune reaction
- Body recognizes bacteria/virus
- Lymphocytes make ABs that seek out and form complexes with antigens
- Complexes are engulfed and destroyed by other WBCs
Three types of biological rhythms
- Ultradian ( < 24 hrs.)
- Circadian ( = 24 hours)
- Circannual ( = 1 year)
Three aspects of rhythm
- Period (length of time to complete one cycle)
- Phase (particular point of cycle)
- Amplitude (difference in value between peak and trough of a cycle)
Three possible hypotheses for lion’s mane
- Protect neck in fights with other males
- Signal of male condition
- Dark manes indicate maturity, increased testosterone, and nutrition
What are some ways that animals can avoid cold or resist cold?
- Avoid cold through body size, appendages, colouration, modification of microclimate, food hoarding, decreased activity, decreased mass, dormancy
- Resist cold by increases thermogenic activity through BMR, NST, and shivering
What is the total amount of heat lost from an animal equivalent to?
What is the approximate measure of metabolic rate?
- The amount of heat conducted from animal’s core to outside of its body
- Slope of 0.75 indicates metabolic rate scales body mass to 3/4 power
What is allometric growth?
- Differential growth of body parts resulting in a change in shape/proportion with increase in size
What is conduction? What is it dependent on?
- Energy transfer through molecular collision
- Must have contact between media involved in heat transfer
- Dependent on: SA of exposure, efficiency of heat transfer through conducting media, temperature difference between two medias