BIO120 Term Test 2

Taxonomic (Morphological)

based primarily on distinct morphological differences

Biological Species Concept

based on infertility (cross ability) among individuals. Yet this doesn't work for asexual species

Ernest Mayer

: responsible for the founder effect, formally defined the biological species concept as "a group of interbreeding natural populations that are reproductively isolated from such groups

Allopatric

mode of speciation, get divergents but then they come back together

Sympatric

mode of speciation within a population, you start to get genetic divergence, get gene flow between species and ancestors which stops divergence. This is quite rare in animals, occurs under specific circumstances

Premating

preventing zygote formation, Geographical, ecological, Temporal, behavioral, Mechanical, prevention of gamete fusion

Douglas Shemske

was particularly interested in these flowers with different than its typical, found premating isolation in species

Post-mating

: preventing the proper functioning of zygotes once they are formed. Inviability, sterility, or abnormal developments of hybrid, F2 breakdown

ex) mule

Hybridization

The exchange of genes between species as a result of occasional inter-specific mating. Varies among different groups of organisms, common plants, fish but rare in mammals, can result in complex patterns of variation

Polyploidy

: an organism, tissue or cell with more than 2 complete sets of homologous chromosomes. Polypoid conditions range from autopolyploidy (AAAA) to allopolyploidy (AABB

Allopolyploidy

(more common) arises occasionally from hybridization between species

Linnaeus

father of taxonomy, binomial nomenclature, hierarchical system: kingdom phyla class orders families genera species

Phenetics

classifying species based solely on overall resemblance. Now largely dead

Cladistics

classifying species on the basis of their phylogenetic relationships

Hennig

invented cladistics and birth of phylogenetic traits which could not provide a depiction of the evolutionary relationships but was a hypothesis.

Monophyletic Group

: single ancestor gave rise to all species in the taxon and no species in any other taxon

clinal pattern of variation

A gradual change in an inherited characteristic across the geographic range of a species, usually correlated with an environmental transition such as altitude, temperature, or moisture.

Non-monophyletic Group

taxon whose members are derived from 2 or more ancestral forms not common to all members

Homology

similarity of traits due to shared ancestry

Homoplasy

similarity of traits because of convergent evolution

Convergent evolution: the evolution of structures that resemble one another and perform similar functional roles due to the shared ecology of unrelated organisms.

W & D Maddison

DNA sequencing is enabling rapid construction of the tree of life. Won apple scholarship and made program and now developed tree of life

Biological invasions

Successful establishment of a species in a region not previously occupied followed by a rapid range expansion. Some are harmful/ some are not

Lome Wolfe

enemy release hypothesis: was interested in possibility that alien species release their enemies when they leave native land. If you go in native range, the level of pest and disease pressure was 17% higher in native range vs introduced, involved both specialist and generalists

Common Attributes of Successful Invasive Species

• Rapid development of reproduction

• Uniparental reproduction (cloning or selfing)

• High reproductive output

• Well-developed dispersal mechanisms

• Broad ecological tolerance

- high phenotypic plasticity

Controls of invasive species

• ¬mechanical (hand/machines)

• Chemical (herbicides)

• Ecological (burning/flooding)

• Biological control

Biological Control

Planned introduction of natural enemies (predators, parasites, pathogens) to control unwanted populations of invaded alien range

Art Weis EBB

studied field mustard seed in southern California in both wet year and dry year. Wet year had many flowers, dry year had barely any, huge year-year fluctuations

Directional selection on flower time

Evidence for directional selection for early flowering in both populations in 2002

Earlier flowering plants set more seed than later flowering plants

Biodiversity

the number and kinds of living organisms in a given area

Background extinction

turnover of species at a low rate, a natural feature of eco-systems; estimated at approx. 1 species/year

2 elements of biodiversity

1. Interspecific variation or species diversity

2. Intraspecific variation or genetic diversity

E.O Wilson

in principle we could fix environmental problems but can't fix the loss of biodiversity. Development is like Spielberg style creation, we barely know anything of it

Mass Extinctions

very large numbers of extinction due to natural catastrophe

Anthropogenic extinction

- caused by humans now estimated 4-6000 species a year (probably significant underestimate)

Minimal Viable Population Size (MVP)

The number of individuals necessary for a species to maintain or increase its number in a region. Smallest population of a species that can sustain itself in face of environmental variation.

SLOSS debate

Debate in ecology and conservation biology during 1970's as to whether a single large or several small (SLOSS) reserves were superior means of conserving biodiversity in fragmented habitat

A generalist species

is able to thrive in a wide variety of environmental conditions and can make use of a variety of different resources (for example, a heterotroph with a varied diet).

A specialist species

can thrive only in a narrow range of environmental conditions or has a limited diet

non-adaptive

lacking in adaptive significance

maladaptive

they reduce fitness, likely in changing environements

tradeoff

ex of Hare with large ears in cold environment, smaller ears=better heat regulation but you compromise hearing activity for predation

Principle of allocation

resources invested in one function unavailable to invest in other functions. The strong relationship between ear size has largely unconstrained by other factors

reproductive-survival tradeoffs

investing resources in offspring means they can't be used in maintaining the body

geographic range

the areas of the planet where the species many be found, usually depicted as range maps

biome level variation

places with more precipitation develop vegetation that is taller, and usually more species rich and productive than places that are drier

soil

formed by the action of living organisms and geophysical processes of some mineral substance that we call "parent material"

parent material

a geologic subject rather then ecological often bedrock, but could be sand deposited in an area by wind and water. becomes greatly altered and added to by biological processes and chemical actions

xeric

very dry soils

hydric

water saturated soil

mesic

intermediate soil

leaching

if rainfall is heavy, dissolved nutrients are carried far down deep aquifers in the soil, below reach of plants

humus

organic matter so decomposed source no longer recognizable

loams

best soils, contain some sand and some clay and plenty of organic matter. The organic matter helps to stay mesic and keep nutrients available

Posoilized soils

cold northern regions, tan, sandy acid and nitrogen depleted

Lateritic soils

lowland tropical, ancient, red clay rich, heavy in iron and aluminum, leached of good nutrients, can support impressive forests but bad for farming

Net primary productivity

refers to the amount of new biomass produced annually through plant growth

dog hair forests

when many seeds start growing at once, from a disturbance, competition for light increases and trees stunted by crowding need to be manually thinned out

terpen resins

are tress principal defense against specialized insects and herbivores

grazing

eating leaves

browsing

eating woody parts

flag trees

branches grow outward only by leeward side of trunk where some buds can escape damage

cushion plants

form dense hemispherical dome of leaves that allows wind to flow over the plant in a smooth flow

ecological speciation

when 2 populations of the same species get different local adaptations because of the different environments they're in, with different selection pressures. This leads to the 2 populations diverging and evolving until they become reproductively isolated and then 2 different species

main problem of Alpine tundra

alpine organisms need to adapt to rapid oscillation of extreme hot and cold and expose organism to extreme UV radiation

evotranspiration

total amount of water that evaporates from terrestrial surfaces or is transpired from plant leaves

potential evotranspiration

that amount of water that could be lost to the atmosphere if that amount of water were available in the system, PE is the measure of the drying up power of the environment

Intertropical convergence zone

aka the doldrums, area encircling earth near the solar equator where NE and SE trade winds converge. the 2 hadley cells meet and the air rises, because the air is so hot and buoyant, then it begins to rise and cool and condense and precipitate (countries in it at all times always get rain aka rain forests)

ecological convergance

plants adapted drip tip to prevent establishment of epiphyll crust, good ex of it

Janzen-Connell hypothesis

supposes that lack of winter in tropical areas means that plants never gain any respite from the attacks of herbivores insects and other enemies such as fungi

Tropical rainforest

is pollinated by animals versus deciduous and boreal is wind

Range shifts

climatically induced range shifts by resident species are usually slow. Dramatic range shifts can occur rapidly when a new species is introduced to region which can become invasive

Warbler- Kirtlands

a small insect eating bird that nests ONLY in forests pf jack pine that have grown after fires that occurred between 5 and 20 years before. This bird is a habitat specialist and very rare, cognitively limited, maladaptive

tropic of cancer

latitudinal lines around the earth at 23.5N

tropic of capricorn

latitudinal lines around the earth at 23.5S

solar equator

line of latitude closest to the sun, oscillates between the 2 tropics lines making 1 cycle per year

atmospheric circulation

solar heating of the bottom of the atmosphere sets up atmospheric circulation patterns

doldrums

windless equatorial area 0-60 going upward or 30 going down

horse latitudes

windless area 30N and 30S

Roaring 40's

too much wind, at 45S

jet streams

concentrated and narrow westerlies and wander in irregular fashion

oceanic circulation

massive packets of H20 produce circulation patterns called currents

Continental climate

large seasonal temperature differences, with warm to hot (and often humid) summers and cold (sometimes severely cold) winters. Usually in the middle of a continent, no body of water to moderate temperature

Maritime climate

typical of the west coasts at the middle latitudes of most continents, and generally features warm (but not hot) summers and cool (but not. cold) winters, with a relatively narrow annual temperature range. Oceans provide thermal inertia which moderates the temperature, great lakes also induce this

orogenic precipitation

mountain generated precipitation

rain shadow

humid air gets pushed by prevailing westerlies to the East from the Ocean. It reaches the mountains and rises. Upon rising it gets cold, condenses and rains/ snows on the mountain. Therefore once air hits the other side of the mountain its dry. Thus you get a large patch east of the mountain where its dry and not a lot of vegetation

limiting factors

factors most important in determining whether a species cannot persist in an area

environmental gradient

the simplest sort of gradient would occur along s line drawn across a real habitat ex) walking from shore to higher ground

thermoconformers

whose bodt temps are more closely track ambient temperatures (fish, amphibians, reptiles)

conduction

direct transfer of heat between 2 bodies that are in contact

convection

heat transfer facilitated by a moving fluid usually air or water

radiation

heat transfer by electromagnetic radiation

redistribution

circulatory system redistributes heat among body parts especially core appendages

SA/V ratio

the way heat is lost only varies with SA not volume

small things have higher SA/V ratio, volume determines how much heat something can hold

Bergmann's rule

homeotherms tend to be larger at higher altitudes (cod) ex) bear, polar bears have big body to hold heat but little SA as more surface area the more heat you lose to environment

Allen's rule

homeotherms tend to have smaller appendages at higher altitudes (colder), they try to have minimum SA/V ratio, like a sphere so they can keep warm. but in hot climates max SA/V ratio try to be flat so they can get rid of heat

countercurrent circulation to limbs

arteries and veins should be appressed in appendages to conserve heat; separated in appendages designed to shed heat.

maintains gradient so heat is always flowing from outgoing to incoming blood

Skinny weasel in cold climate: tradeoff

being long and thin makes weasels subject to thermal stresses, but they need to be thin so they can go into the burrows of their prey, a compromise for food