Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
89 Cards in this Set
- Front
- Back
|
niche theory |
Explains Biodiversity of communities. Species fit into niches to allow for coexistence. Core principles: species compete either strongly or weakly for resources. species are better adapted for certain conditions than others, those that compete weakly have weak overlapping niches and will have higher fitness. |
|
|
neutral theory |
species-rich communities occur because of random determined processes that include death, immigration from a regional pool of species, and speciation. core principles: all individuals in a community of trophically similar species are ecologically identical, what species will be present and persist is random. |
|
|
zero sum assumption |
apart of neutral theory, says that if the community is full, a new individual can only establish if another one dies and makes space. However, this doesn’t mean that a community must be full. |
|
|
Hoffmann |
Made paper from red listed (threatened or endangered) vertebrates (birds, mammals, reptiles and amphibians, and fish) to determine the effects of conservation effort. |
|
|
Anthropocene |
a period in which the world’s flora and fauna are dominated by human activities |
|
|
International union for the conversation of nature IUCN |
From their research the state of biodiversity is decreasing based off of habitat extent and condition and community composition. Pressure on biodiversity is increasing, (ecologogical footprint, nitrogen disposition, number of alien species, overexplotation and climatic impacts). Human Responses to try to mitigate biodiversity loss is also increasing( protected area extent, biodiversity coverage, responses from alien species, sustainable forest management and biodiversity related aid) |
|
|
Cascade effect |
the removal of an apex predator causes a greater abundance of meso-predators. Ex. bull shark and tiger shark are in dramatic decline in the last 30 years. the meso predators such as small sharks and sting rays are increasing due to their predators being eliminated, however this causes a greater loss in molluscs and bivalves |
|
|
3 ethics that created Conservative biology: |
1.The romantic trancendental conservation ethic - nature has a intrinstic value that does not need to be justified, nature was a way to clenase the soul. 2.The resource consevation ethic - gifford pinchot willing to exploit a resource which may negatively effect species, however to do it in a susptainable fasion since it has resource value. 3.Evolutionary-Ecological Land Ethic – Aldo Leopold land, water and organisms were intrinsically linked in a dynamic balance. |
|
|
gifford pinchot |
created The resource conservation ethic willing to exploit a resource which may negatively effect species, however to do it in a susptainable fasion since it has resource value. |
|
|
Aldo Leopold |
created the Evolutionary-Ecological Land Ethic land, water and organisms were intrinsically linked in a dynamic balance. |
|
|
paul herbert |
Created Next generation sequencing -the intra (within species) variation of mitrochondrial DNA sequence section is very minimal, however inter is very differnt, that allows the the detection of species within a environment, if the sequence is detected the speices must be present within the water environment |
|
|
the 2 main objectives of Conservation Biology are: |
1. to investigate human impacts on global diversity2. to develop practical approaches to promote human development (including resource exploitation) without extinguishing biological diversity |
|
|
Precautionary principle |
it is easier to prevent environmental dmaage than to fix damage. To prevent damage We must shift the “burden of proof” away from those advocating protection to those proposing actions that may be harmful (e.g. hunting, mining, logging, farming). |
|
|
Core principles of conservation biology |
1.Evolution is true, and it unites all of biology.2.The ecology is dynamic and non equilibriual, populations are always fluxuating 3.Humans presence is important to conservation planning. |
|
|
bio-geography |
the study of distributions of species over space and time. there is descriptive bio-geography and ecological bio-geography. |
|
|
geographical realms |
are large spatial regions within which ecosystems share a broadly similar biological evolutionary history. Eight terrestrial biogeographic realms are typically recognized, corresponding roughly to continents |
|
|
Uniformatarianism |
n idea formed by Lyell that processes today are identical to those operating in the past. It is that concept that allows us to infer history from observations made in contemporary time. ex. darwin's idea of evolution |
|
|
Allen's rule |
warm blooded animals will have more compact extremities in cold climates than in warm ones. |
|
|
Merriam’s life zones |
means of describing areas with similar plant and animal communities. Merriam observed that the changes in these communities with an increase in latitude at a constant elevation are similar to the changes seen with an increase in elevation at a constant latitude.
|
|
|
Holdridge |
modified merriam’s life zones to include precipitation, biotemeperature and potential evaporation which made this system useful for predicting environmental changes. |
|
|
The 2 discoveries that influenced biogeography were |
the idea of continental drift and the relationships between diversity, island size and distance from mainland relationships |
|
|
Continental drift |
devised by wegner in 1912 |
|
|
250 Million years ago |
Pangaea exists. distributions of current species have been far more influenced by events since the break-up of Pangaea than anything which occurred before its formation. |
|
|
3 kinds of barriers important in restricting large scale distributions of groups of organisms. |
1. Oceans2. Mountains3. Large variations in climate |
|
|
In Canada the separation of realms and species distributions is caused by: |
1.The rocky moutnains seperating the east from the west 2.Glaciation form the pleistocene which affects both the physical environment and the species distribution3.The land bridge that connected north america and Asia at the bering strait |
|
|
Evidence that supports continental drift |
1.Fossil record of species that had minimal migratory abilites on opposite sides of the world 2.Rocks of similar minerology, thickness and age ( i.e. Lithology) on opposite side of the earth whcih align if pieced together like a puzzel 3.Paleomganetisim of rocks formed with simular ages on other side of the planet also have similar magnetic orientation, which are different from today, suggesting that the rocks have moved since they were formed. 4.The formation of volcanic island as plate move. The oldest islands correspond to the location of the plates at the time of formation. |
|
|
Disturbance |
Any relative discrete event in time that removes organisms and opens up space which can be colonized by individuals of the same or a different speciesDisturbances can be short or long-term, predictable or unpredictable, and intense or not intense |
|
|
Maximum diversity expected at... |
mid-levels of natural disturbance. High disturbance sites tend to be inhabited by a few colonizing species, low disturbance sites dominated by a few excellent competitors. |
|
|
Krakatoa |
a volcano that blew a part the large island in Indonesian, creating 2 separate islands, one which didn’t exist before called Krakatoa Anukrakatoa eruption caused half of the island to sink. anak krakatau island is the top of the volcano |
|
|
Founder effect |
Small founding populations that colonizes an island has only a fraction of the allele frequency/diversity that the original population had which, in turn, can cause a genetic bottleneckThe reduced genetic diversity in the founder population can also give rise to random genetic drift |
|
|
Genetic drift |
random shift in gene frequencies, small populations are more preseptable to genetic drift. Genetic drift can lead to significant changes in a species genetic makeup even without further adaptation |
|
|
Five ways evolution occurs: |
Founder effectGenetic driftMutation ( always is occuring)Dispersal ( plays less of a factor in really remote areas and for species with low migration ability)selectionOn Islands the founder effect and genetic drift play the largest factors for evolution on islands. |
|
|
3 peculiarities that occur on islands |
1. Dwarfism or Gianticism 2. dispersal 3. Ecological release |
|
|
insular dwarfisim, insular gigantism |
2 patterns of phenotypic variaiton for island populations. Compared to the populations on the mainland, island populations tend to become smaller if there size is large on the mainland(insular dwarfisim), and those that tend to have small body size on mainaland were larger on islands(insular gigantism). |
|
|
3 hypothesis to explain the dwarfism/ gigantism |
Predation pressures- larger size due to lack of predation or smaller size due to higher predation pressures Social- sexual hypothesis - larger body size may occur for intraspecific competition for mating rights due to high densities that occur among island populations Food availablity hypothesis - less resources = pressures for smaller body size |
|
|
he speckeld rattlesnake |
an example of dwarfism/ gigantism. speckled rattlesnake colonized island first, became larger potentialy to fill larger prey niche. |
|
|
Island perculiarity 2. dispersal |
Many species tend to loose their dispersal ability over time, this may be advantages to insure that the offspring of the species will continue the population on the island. Ex. Seeds travelling less distance will remain on the island to create then next generation, if no seeds remain on the island then there will be no next generation |
|
|
Island perculiarity 3. Ecolgoical release |
Due to reduced competition or from other interacting organisms like predators lead to 2 changes:1.The loss of unecessary features on the island, like flight, defeneses, costly sexual fitness displays.2.Many species lost the fear of humans. Ecological release may have lead to adaptive radiation since the islands species would have also been released from close competitng species. This would allow colonists to occupy different niches and also a wider variety of niches than those on the mainland. |
|
|
Adaptive radiation |
Rapid diversification in morphological or behavorial aspects of a lineage following colonization of a new habitat due to new opportunities to fill new niches, diversification can suometimes lead to new species. ex. Darwins finches or the hawaiian honeycreepers. Cichlid fish species living in lake malawi in africa half live on rocky bottom conditions and half live on sandy bottoms, they also vary in diet and colors but genetically speaking these fish split from only 2 genetic lineages. |
|
|
Hybridization or introgression |
When two genetically distinct species are still able to mate with each other then this infuses new genes into the population and the 2 species are no longer isolated from each other and the distinguish between the 2 species can decrease. Dawrin’s Large finch species colonized from Santa Cruz, but has since hybridized with medium finches, and mating evidence exists of small and medium finches fusing as well. So it is possible three species will eventually merge into one. This hybrid species may be less vulnerable to diseases and parasites and the 3 distinct species. |
|
|
Paleoendemics |
species that had a board range, but abundances became reduced due to an environmental change. is now an endemic species |
|
|
Neoendemics |
species that evolved and stayed on the island. |
|
|
Species-isolation relationships |
decline of biodiversity with distance from mainland. Distance prevents disersal limted species from colonizing. Ex. There are no native mammals, reptiles or amphibeans on hawaii, only some flying insects and plants. |
|
|
new guinnea |
has more biodiveristy than expected because it has more habitat patches than expected because of its mountainous terrain. Biodiveristy may also be higher because certain species require a habitat patch to be a larger size than what the isolated island can have. |
|
|
Species- area relationships |
The more area, the more species the island can have. the relationship between log area and log diversity is linear. |
|
|
Darlington |
created the empirical relationship between Island area and number of reptile and amphibian species in the West Indies. it is called the power line equation. S = CA Z s = species, C = a constant that varies with taxomic group, climate, isolation and other factors. |
|
|
What happens to S when we fragment the habitat? |
As habitat area shrinks, some species immediately go extinct. However, the ‘relaxation’ process may take thousands of years to unfold, as extinction debt become apparent and S declines to its final value, potentially genetic drift may become a problem and inbreding.habitat loss on an island affects the diversity more than on a continental patch because of the curve of a island has a higher slope for diversity vs. area, than continents. # species on islands decreases more with decreases in area than continetal species. |
|
|
problems with Lower law for species area relationships: |
tends to overestimate initial extinction and the delayed extinction is underestimated Equation tends to underestimate diveristy of small habitat areas may overestimate extinction rate from habitat loss. ( mis-repesentation for sampling grid for rare species) |
|
|
other factors that influence the number of endemic species... |
more time = more species from immigration, speciation fewer micro-habitats = less diversity |
|
|
Secies abundance relationships |
Common species are few, but have high abundances, there are many rare species. Veil Line is the abundance below which we cannot detect a species that is present. We can sample more to see if we can find them. |
|
|
Species turnover |
the equilibrium value for the island is proportional to the number of immigrants that come to the island, and the loss of individuals due to emigration and extinction Ex. After krakatoa explosion there was a rapid increase in bird species until 1920, after that number of species remained constant, but newcomers replaced those already present |
|
|
Island equilibrium theory |
proposes that the number of species inhabiting an island is based on the dynamic equilibrium between immigration and extinction.St+1 = St+I+V-E St is number of species at time tI is the Immigration rateV is additions through evolutionE is losses by extinction |
|
|
Diagram rate vs. diversityNear islands have most immigration.Small islands have most extinction lowest diversity = far small islandshighest diversity = large islands close to mainland Species turnover rate is highest on small (high extinction), near (high immigration) islands Turnover lowest on large (low extinction), far (low immigration) islands |
|
|
Simberloff |
tested equilbirium theory on mangroves “habitat islands” The farther islands maintained a lower species number according with the equilibrium theory (lower Immigration). |
|
|
Critisims of equilibrium theory of island biogeography |
somes species occur in an area at different times, this means that their ecology is vastly different from other species that could be present since they require different environmental conditions, this theory ignores the differences between species ecology |
|
|
Vicariance biogeography |
alternate model of biodiversity formation on islands. It says that when one continous habitat with one species present is split and isolated the species will evlove sperately under different selection pressures with or without founder effect or genetic drift. A new species may form. |
|
|
rescue effect |
becasue the island is close to the mainland =, a population on an island that has been decresased because of some event, members from the mainland can rescue that population by flying over to the island and bringing genetic diversity back |
|
|
Transient species |
species that migrate and have large ranges |
|
|
reversing defaunation: restoring species in a changin world |
by seddon |
|
|
seddon's paper |
reviews the full spectrum of conservation translocations, from reinforcement and reintroduction tocontroversial conservation introductions that seek to restore populations outside theirindigenous range or to introduce ecological replacements for extinct forms |
|
|
2 types of population resotration by Rleasing animals into ther indigeous range: |
Reinformment - releasing an organisim into an existing population to enhance population viabilityRe-introductions- re-establish a population in an area where local extictin occured. |
|
|
Reintroduction outcomes have generally low sucess rates because |
To have higher sucess must have larger founder group sizes to mimize inbreeding and bottlenecking. The population required for preservation of genetic diversity may be substantially greater than that requore for population establishment and growth. However, larger populatons also bring density dependant restaints on populations such as disease. |
|
|
assumptions about what is the target state |
Have to assume that past numbers are population numbers that are sufficent nowadays in the face of climate change. |
|
|
2 types of conservation translocation outside geographical range. |
assisted colonization |
|
|
assisted colonizatio |
Thought to be risky since is basically introducing an invasive species to a new habitat hoping it will colonize and develop a healthy population. Need to do a quantitative risk analysis before performing. Ex. The kakapo the flightless engandered paroat species has been colonized on predator free islands. The selection of suitzable habiat must match the biotic and aboitic needs of the species under future climate scenarios. |
|
|
Rewilding |
Translocations with the primary objective of restoring ecosystem functions, may be reintroductions or ecological replacement which is the introduction of a new species to an area to take over a vital ecosystem fuction role ex. The ectiction of endemic giant tortisose on madagascar ment that seed distrubtion was distrupted, the introduction of other giant tortoses helped restore this seed distrubtion.. The future challenge is the identificationof suitablereplacements to perform the desired ecosystemfunctions within a given system. Thelonger the time since the extinction of the originalform, the greater the uncertainty about thebest substitute. |
|
|
Biodiversity can increase ecosystem stability by |
buffering the effects of environmental change,resisting species invasions, and preventing secondaryextinctions after species losses |
|
|
Singleton |
species with only a single individual in a sample |
|
|
Uniques |
species that have been collected only once (including multiple samples) |
|
|
rank abundance curves |
# of individuals versus rank |
|
|
Rabinowitz |
described a general pattern of species abundances in which there were 3 different ways that species could be rare. speices that are most at risk are those that are rare everywhere, have a samll range and are specialist. most rare species were those that were specialists the rarest way to be rare was that the species had low pop size |
|
|
Rapaport's Rule |
high tropical diversity is associated with habitat specialists and small geographic ranges |
|
|
Individual-Based Rarefaction Curve |
Curve show accumulation of species as a function of number of ind. counted. the asynptotic value represents 100% # of species. |
|
|
Sample-Based Rarefaction Curve |
Diversity increases both with the time spent per survey (sample) and with the number of surveys (samples). All lines approaching an asymptote (true diversity). |
|
|
Those that were found in all 4 seasons... . Those found in all 5 lakes tended to be abundant, those that were rare were typically only found in one lake. |
...tended to be the most abundant species. |
|
|
International Union for the Conservation of Nature (IUCN) indicators to determine which species are rare and at risk of extinction are |
1) rarity;2) rate of decline (high rates being bad);3) degree of population fragmentation. |
|
|
n the IUCN model, species are considered critically endangered in terms of geographic range |
if the extent of occurrence is <10km2, |
|
|
severe fragmentation (many small, isolated populations) and lack of fragmentation (a single or few subpopulations) |
can be considered as indicative of increased risk of extinction. |
|
|
protection of habitats and ecosystems are th best aproach to perserving biodiversity however, umbrella species.. |
act as a umbrella and other species in their habitat will also be protected.ex florida panther |
|
|
good candidates for introduction into areas outside their current distribution in the form of assisted colonization are... |
Species rare due to limited geographic distribution, but with fairly generalized habitat requirements and high local abundance |
|
|
UCN (2013) defined assisted colonization as |
the intentional movement of individuals outside of their indigenous range to avoid extinction from current or future threats. |
|
|
Rare species (plants) have: |
lower levels of self-incompatabilitygreater tendency to asexual reproduction, lower overall reproductive effort poorer dispersal abilities. |
|
|
How can we detect rare species? |
Spectral analysis of vegetation cover to identify stands of invasive plants As sampling effort or density increase, the probability of detection increases Use of DNA to detect rare aquatic species |
|
|
species focused conservation: Species concept of conservation has been questioned because: |
Recent advances in molecular genetics introduce questions of genetic identity. Are wolves in Algonquin Park eastern wolves (Canis lyacon) or grey wolves (Canis lupus) or even coyotes (Canis latrans)? If it is a mix, should we protect it? Some argue that species-based conservation efforts may be misplaced since they are biased in favour of mammals and birds at the expense of other microscopic or unattractive taxa; and that the basis should be ecosystem oriented. . Others suggest conservation of 'endangered phenomena', such as that of migrating populations of monarch butterflies, is necessary. 15-year downward trend in population of migrating monarchs due to loss of wintering habitat in Mexico and breeding habitat in USA, loss of milkweed host, and bad weather Population biologists question whether the species is the appropriate conservation unit. Should we preserve genes & gene complexes, or evolutionarily significant units (like a particular lineage)? |
|
|
florida panther example |
Protection of the ecosystem or the species? Is the Florida panther worthy of protection? - it is now a hybrid species counter aurguments: |
|
|
Species Concept: the Historic or Typological View: |
species viewed as having fixed characters; variation is considered unimportant, unfortunate and unusual. Type specimens define the characteristics. focused on the "norm" |
|
|
Population or Evolutionary View |
Variation is intrinsic to species and is important since it is the raw material through which natural selection and evolution (speciation) occur. This view accepts geographic variation as important in adaptation and speciation. |
|
|
a species by definition is |
a group of actually or potentially interbreeding organisms separated from other such groups (Ernst Mayr). |
|
|
chronospecies |
- species that occured in the past may look the same, but they are gone now so we cant bred them.. so are they different species or not? |
