BISC 363 Final Exam
vicariance or dispersal can result in...
(1) DISJUNCT DISTRIBUTION (2) SPECIATION
how many biomes and biogeographic regions are there?
- 14 biomes - 8 biogeographic regions
example of vicariance?
- 2 species of antelope squirrels diverged due to population split on either side of Colorado River in Grand Canyon
What is responsible for biogeographic regions?
- Continental Drift (present extent of the major tectonic plates and the direction of their movements) - came after biogeographic description of species
what is a species that practices altruism?
- Desmodontinae (vampire bats) - share blood meals with roost - may starve if no meal for 2 consecutive nights - begging can save life - happens when: > donor loses 5% of body mass (= 6 hrs of time lost) > recipient gains 5% (= gains 16 hrs of time)
key concepts of life history tables
- Ix (probability of survival to next year) and Mx (reproductive output) - life history (patterns of reproduction and survival) is complicated - tradeoff b/w survival and reproduction (more energy spent on one means less for the other) - life history tables are never stable (vary based on environmental carrying capacity, species, etc)
caching behavior of Dipodidae?
- K rats use external cheek pouches to transport seeds for caching - actively manage cached seeds > control degree of fungal growth > diet diversification > prevent germination
optimal foraging strategy
- Natural selection should favor foraging behaviors that deliver the highest payoff with minimal cost
human persistence hunting
- San tribe hunt large ungulates through endurance hunting (1) target large usually male prey (2) chase (3) track (4) repeat over next ~8 hrs (5) wait till exhaustion of prey
olfactory signal receiving?
- Vomeronasal organ (VNO) > AKA Jacobsen's organ > important in receiving sexual pheromones - Flehmen behavior (ungulates and carnivora)
how did rinderpest virus in Wildebeest influence an entire ecosystem?
- Wildebeest populations suffered from virus - virus eradicated in 60's resulted in population explosion - reduced grassland from grazing reduced fire severity - taller trees could grow and allowed for giraffe populations to increase
what are some components that affect individuals in a population?
- age - size - sex - behavior - development - growth - feeding - reproduction - death
what are some components that affect a population in a community?
- age distribution - sex ratio - spatial distribution - density - population growth - survivorship - demographics
anti predator behaviors?
- alarm calls - defense (kicking, horns/tusks/antlers)
what is the genetic basis of selection with respect to environment? discuss a study of this...
- alleles at different frequencies may be the result of selection - in Peromyscus maniculatus (deer mice), 2 very different alleles of a gene correspond with altitude (H and L) - Epas1 is a hypoxia-inducible factor transcription factor (modifies expression of other genes induced by low O2 levels) - animals carrying different alleles exhibit different physiology - similar findings in Tibetans
ambush vs other hunters?
- ambush = solitary > ex. Felis concolor - group hunting > ex. Panthera leo
how do vertical temperature gradients influence mammalian biotas
- as elevation increases... > temp decreases > O2 decreases > precipitation increases - desert assemblage of mammal species occur at base (lower) while boreal assemblage exists higher up
what are communication signals?
- behavioral, physiological, or morphological characteristics fashioned or maintained by natural selection that convey info to other organisms - can be visual, olfactory, auditory, tactile, or combo
latitudinal species gradient
- biodiversity is richest near the equator > tend to have higher speciation rates > lover extinction rates > accumulate more species OPPOSITE PATTERN HOLDS TRUE FOR CETACEANS AND PINNIPED DIVERSITY
fossorial foraging
- build complex underground burrowing systems - burrowing is energetically expensive - burrowing patterns cover max area with least effort - ex. mole rats burrow longer tunnels in moist soil (peak activity) and short branches when soil dries
allomone purposes?
- chemical signal that elicits a response in a receiver of a different species - may convey unique messages - dispersed in air over long distances
what causes competition? What are some ways of alleviating competition?
- competition depends on degree of niche overlap - alleviating competition: > niche differentiation > competitive exclusion > foraging guilds
urine and fecal signal purpose?
- convey info about physical condition - establish and maintain territory boundaries - males recognize females in estrus - help establish reproductive synchrony among herd/pack - may provide additional cues about spatial orientation to members of group
importance of allogrooming?
- convey info on social status - reinforce social bonds - dissipates aggression - ritualized greetings
what effect on herbivores does plant defenses have?
- deactivation of chemical defenses is costly to herbivores (takes lots of energy) - must balance between intake of nutrients against intake of defensive compounds - some defensive compounds are altered by microbial action - mammals have also evolved behavioral and morphological adaptations to 2ndary compounds > selective foraging > reduced metabolic/reproductive rates (slow loris) > adaptation of intestinal, cecal, or rumen microbes
what are food webs?
- describe the complex pathways of energy transfer in nature - shows how energy is lost at each level - total available energy is largest for consumers at lower levels
what are some approaches to zoogeography?
- descriptive and static (what occurs where) - ecological and historical (what occurs where and for how long) - integrative (prior 2 plus how relates species have colonized other places)
alleviation of competition and foraging guild example?
- different sizes of heteromyids specialize on different size seeds (resource partitioning) - even though there are 4 distinct desserts in CA (geographically isolated), their assemblage of species (granivorous rodents) is very similar (i.e. similar distribution of sizes) - tells us competition has been alleviated and various subspecies can coexist by partitioning resources
how can we compare the sauteur rabbits to species distribution of shrews with altitude?
- different species of shrew occupy different altitudes and their respective habitats - sauteur rabbits have humans as their selective force - selective force of shrews can be any number of factors (precipitation, vegetation, O2 saturation, predation, etc.)
what are some visual signals seen in domesticated dogs vs wolves?
- dogs have prominent LAOM and RAOL to allow them to raise their eyebrows (puppy dog eyes) - wolves have very minute or absent muscles
ultrasonic signaling?
- echolocation in bats/dolphins - reproductive signals in rodents (sexually associated behaviors)
pheromone purposes?
- elicit response in conspecific receiver
what is the purpose of visual signals of various bovids?
- facial markings act to extend line of horns onto the face
who was Alfred Russel Wallace?
- father of biogeography - co-discoverer of evolution by natural selection (with Darwin)
communication of Didelphis virginiana?
- feigning death - many visual/olfactory signals: > body stiffens, tongue out > drools > foul odor exuding from anal glands
scatterhoarding
- few food items stored at many locations throughout the territory - adaptive only if cache remains intact and not lost to conspecifics or thieves - costly (requires GOOD MEMORY!) --> large hippocampus
communication of many antelopes and cervids?
- flagging of tail (underside white to signal alarm when raised) - stotting: NOTE that it makes prey more visible and uses time and energy, continued performance must have some benefit
k-rat defense from predators?
- foot drumming - sand kicking - backwards jump - karate chop
Heterocephalidae social structure?
- form colonies with single female member breeding - remainder divided into social castes with morphologically distinctive individuals for specialized labor > frequent workers > infrequent workers > non-workers
acoustic signaling?
- hearing in mammals is acute - auditory communication is very important > continuous noises made by herd/troop members keep individuals in tune with each other - vocal ranges species to species (short calls to large vocal repertoire) - alarm calls can be predator specific - contact calls may serve as territorial advertisements, maintain group cohesion, ID individuals
how do beavers influence their environment? Yellowstone example?
- heavily influence water flow from dam creation - Yellowstone... > in areas where wolves are present, less elk are abundant, willows grow more, beavers love willow > INTERSPECIFIC RELATIONSHIPS CAN HAVE HUGE IMPACTS ON LANDSCAPE
tactile signals?
- includes: > precopulatory behaviors (nuzzling, nibbling) > flipper rubbing in dolphins > allogrooming
rain shadow effect
- incoming warm and moist air from the ocean is drawn from prevailing winds towards mountain tops - air condenses and precipitates before crossing the top - dry air advances behind mountains creating a drier side - ex. Sierra Nevada in CA from Pacific Coast - W basens receive higher precipitation, E slopes receive lower (often deserts)
Indo-Malay region
- isolated by Himalayas, deserts, and ocean - tropical climate dominates (rainforests) - 49 mammalian families - 8 ENDEMIC > Moschidae > Tarsiidae > Tupaiidae > Ptilocercidae > Cynocephalidae > Hylobatidae - shares 90% of families with Palearctic
Brief description of changing landmasses from Early Jurassic (195 mya) to Holocene (present)
- late Jurassic: > migration of landmasses into 2 major subcontinents (Laurasia, Gondwana) > Africa connected to Antarctica (which was not covered in ice) - late Cretaceous: > further migration, fragmentation yielded modern continents - early Paleocene: > explosive adaptive radiation of mammals > Australia still broadly connected to Antarctica - Middle Eocene: > NA connected to Asia > climate change - Middle Miocene: >NA and SA coming closer together > ice sheets over Antarctica - Late Pleistocene: > major ice sheets > continents in contemporary positions - Holocene: > present
Visual signals of Cercopithecidae
- male mandrill have brightly colored face and genital region to advertise dominant status - structural coloring produces blue color (physics of light interference)
what do plants and animals rely on each other for?
- mammals depend on plants for food/shelter - plants depend on mammals for seed dispersal/pollination and increased seed germination
larderhoarding
- many food items stored at a central site within the territory (large hoard in 1 place) - doesn't need to remember where, but need to protect - more problematic if raided
scent marking purpose?
- maturation and use of scent glands controlled by gonads produced at sexual maturity - mostly done by dominant males - often associated with territory possession - deer have multiple glands that
ultrasonic signaling in mice?
- mice give off different ultrasonic songs depending on their behavior
effect of mammals on environment: Bats
- modify insect populations (remove herbivorous insects from tropical plants) - help pollinate - seed dispersal (fruit bats help regenerate tropical forests)
Canidae hunting strategies?
- most solitary, cursorial hunters - others hunt in packs - highly adaptable - capture prey by virtue of speed or endurance - learn though experience - keen sense of smell (often detect prey by windborne scent)
caching behavior
- moving of food to storage site for consumption at a later date - protection of food - protection from predators while eating - steady supply during lean times - toxins can be reduced over time (pika!)
what is coevolution?
- mutual influence of evolution on 2 species interacting with each other and influencing each other's adaptations
Antarctic region
- no land mammals - seals and other marine mammals live along edge of continent
Oceania region
- oceans of the world and isolated islands - only land mammals are bats and commensal rodents - MARINE MAMMALS - oceans much more homogeneous from basin to basin due to broad connections and greater potential for global dispersal
unique foraging method of orcas?
- one population exhibits "beaching" behavior - one population uses "wave hunting" in the arctic
what is Altruism?
- organism acts in manner that temporarily reduces its fitness while increasing another's fitness, with expectation it will reciprocate later - short term cost is offset when recipient returns the favor - evolves when at least 1 is met: (1) donor and recipient recognize one another (2) donor and recipient genetically related (3) repayment is likely (4) benefit to recipient > cost of donor
how have koalas adapted to eat eucalyptus?
- particular gene family in koalas involved in metabolic breakdown of toxins has duplicated many times over in their genome - possible basis for how they can detoxify eucalyptus
describe the relationship between diet quality and mammal anatomy:
- plant material is more difficult to digest --> digestive tracts longer and more complex in herbivores - insects/meat are good energy sources but plants are more available (less nutritious)
what are the 3 levels of ecological study?
- populations: individuals of the same species living in the same area @ the same time - communities: interactions b/w populations of different species (predation, competition, mutualism) - ecosystems: interactions b/w 100s to 1000s of species (plant/animal) over broad geographic areas
Hunting Prey
- predators have evolved behaviors to facilitate the pursuit, capture, and killing of live prey - ambush or solitary predators
why would eusociality have evolved?
- probably in response to ecological restraints > droughts common (food scarce) > extensive burrow system needed to find food > colonies required to dig burrow and find food
olfactory signals?
- scent marking - urine/fecal signals - pheromone - Allomone
effect of mammals on environment: Sea Otters
- sea otters prey on sea urchins along Alaskan coasts - help maintain kelp beds - KEYSTONE SPECIES
Nearctic region
- separated by Bering Sea, recently connected to SA via Panama Land Bridge - arctic tundra and semitropical thorn forests, minimal deserts - 30 mammalian families - 2 ENDEMICS (aplodontia and antilocapridae)
Palearctic region
- separated by Himalayas, Bering Strait, and deserts - primarily temperate climate (boreal forests, broad leaf forests, Mediterranean forest, grasslands, some deserts) - 36 mammalian families - NO ENDEMIC FAMILIES
Australasia region
- separated by ocean - dominated by tropical forests, savannas, deserts - 35 families - 21 ENDEMIC - closest affinities with other mammals from this region - CENTER OF DIVERSITY FOR MONOTREMATA AND METATHERIA
what causes global climate patterns?
- solar radiation (ununiform across the Earth's surface, intensity varies due to tilt of planet) - warm air holds more moisture (equatorial areas are more tropical 25N to 25S) - cooler air carries less moisture (major deserts located around 30N and 30S)
foraging using tools
- some mammals use rocks or similar tools to break open prey - mongooses, skunks, sea otters (mustelids, mephitids)
infrasonic signaling?
- sounds produced below human hearing range - Elephants use low frequency vocalizations to locate each other, signal aggression, convey reproductive cues
vicariance
- species distribution split by natural barriers - results in geographic isolation - phylogeny often influenced by vicariance events - mutation occurs in split populations and lead to diverging groups - while dispersal is ACTIVE, vicariance is PASSIVE
what are some components that affect communities?
- species diversity/ interactions - food webs - feeding guilds - energy glow
what are some plant defenses from herbivory?
- spines/thorns/irritating hairs - secondary compounds (toxins, inhibit digestion, antimicrobial action on gut microbiomes)
Giving Up Density
- strategy to study behavior invented by Joel Brown - animal has to work to get food out of trays - as they become more uncomfortable (predators, disturbances, time of day, season) they will give up more food
what is zoogeography?
- study of animal distribution
dispersal
- subpopulation of a species actively migrate across a geographic barrier to form an incipient species and eventually diverge into a new species
N vs S facing slopes
- sun rays hit S facing slopes more directly (are considered drier and warmer with different biotas)
***Plate tectonics explain ___
- the diversification of the major placental clades (1) Afrotheria (2) Xenarthra (3) Laurasiatheria (4) Euarchontoglires
effect of mammals on environment: Wildebeest
- transform and maintain grasslands of Serengeti plains (seasonal migration) - Thomson's gazelles graze in areas with new growth - wildebeest are KEYSTONE SPECIES
Neotropic Region
- tropical or subtropical (some deserts, alpine tundra, savannas) - central Mexico to SA tip - 56 mammalian families - 29 ENDEMIC FAMILIES! - characteristic of region: > marsupials > bats > primates > xenarthrans > hystricognath rodents
Afrotropic region
- tropical savannas, tropical forests, montane forest, alpine tundra (barely), deserts - 58 mammalian families - 20 ENDEMIC > 8 endemic to Madagascar (Lemuridae, Tenrecidae, Eupleridae, Daubentoniidae, Indriidae, Myzopodidae, Cheirogaleidae, Lepilemuridae) - HIGH DIVERSITY OF UNGULATES - Last important stronghold of: > Equidae > Rhinocerotidae > Elephantidae > Hippopotamidae
unique foraging method of Humpback whales?
- use of bubble nets to trap schools of fish - extremely smart, learned and taught among single population
when is endurance hunting used?
- usually for chasing down weaker prey (old, sick, very young) - ex. wolves
unique foraging method of otter shrews?
- water "sniffing" - blow air bubble, touch it to prey item, sniff bubble back in
which region has the most families of mammals?
Afrotropic (58)
common larder hoarding families?
CRICETIDAE (& some sciuridae)
ultimate form of altruism?
EUSOCIAL MAMMALS! - give up reproduction to assist another individual - only seen in 2 mole rat species - Heterocephalidae uses pheromones to suppress other females from breeding
which region has the most endemic families?
Neotropic (28)
springbock communication
PRONKING! (bovid family)
who are some common scatterhoarding families?
SCIURIDAE! - Sciurus niger - Tamias merriami
what's the most commonly cached food?
SEEDS! - concentrated energy source - can remain dormant for long periods
What is the Wallace Line?
The line separating the flora and fauna between Asia (Indo-Malayan) and Australian (Australasian)
what is phytogeography?
combined study of phylogenetic relationships b/w species and their distributions
what's significant about the Wallacea islands?
group of islands not connected to land masses of either content so only populated by mammals capable of crossing H2O
what are foraging guilds?
group of species that feed on common resource in a similar manner
in general, nearby regions tend to harbor ___ than regions farther away
more similar families
what results from alleviating competition?
resource partitioning and microhabitat segregation
what is biogeography?
study of distribution of organisms in time and space
what is ecology?
the study of animals and plants and their relation to each other and their environment