18: Classification, Biodiversity + Conservation Flashcards
What are the causes of extinction?
- lack of food sources
- alien species outcompete
- climate change causes temperature increases above species tolerance (like coral reefs in the oceans) -> particularly bad for specialist species (those with a narrow niche)
- human activity - loss of habitat (draining wetlands, deforestation, pollution of the air, water + soil), hunting and close proximity to species introduced new diseases and species
- natural disasters
What is a biological species?
A group of organisms with similar morphology and physiology which can breed together to produce fertile offspring and are reproductively isolated from other species.
What is a morphological species?
a group of organisms that share many physical features that distingush them from other species
What is an ecological species?
a population of individuals of the same species living in the same areas at the same time
Define population.
all the organims of the same species in the same place at the same time that can interbreed with one another
Define community.
all of the living organisms, of all species, that are found in a particular ecosystem at a particular time
Define niche.
the role of an organism in an ecosystem; how the organism ‘fits’ into the environment
Define ecosystem.
a relatively self-contained, interacting community of organisms and the environment in which they live and with which they interact
Define habitat.
the place where an organism lives, a population or a community lives within an ecosystem.
What is the classification system?
species -> genus -> family -> order -> class -> phylum -> kingdom -> domain
What are the 3 domains?
- bacteria
- archaea
- eukarya
What are the 4 kingdoms of eukarya?
- protoctista
- fungi
- plantae
- animalia
Define biodiversity.
the variety (number and range) of ecosystems and habitats and species in an area and the variation, genetic diversity and abundance within each species.
What is species richness?
no. of different species present
What is species eveness?
similarity of abundance of the species present
What is species diversity?
all the species in an ecosystem
* species richness
* eveness of abundance
What is genetic diversity?
all the alleles of all the genes in the genome of a species
Ecological reasons for maintaining biodiversity?
- higher diversity = less likely to be unbalanced by changes in conditions (e.g. pollution, loss of a species)
Economic reasons for maintaining biodiversity?
- medicines orginiate from living organisms (antibiotics from fungi and bacteria, anti-cancer drugs from Madagascan Periwrinkle + Pacific Yew Tree)
- medicines can be mass produced
- need to protect in order to keep potential drugs alive = maintain gene pools, keep wide range of alleles
- ecotourism - national parks
- Thermus Aquaticus in PCR
- mangroves protection from tsunamis and help with flooding, coral reefs act as sea defense
Agricultural reasons for maintaining biodiversity?
- crop plants are not genetically diverse due to being so selectively bred, so biodiversity needs to be maintained in order to widen crop plants genetic diversity if need be (say current crop is affected by disease)
- so in the case of extinction, there are other relatives of the crop to use
- pollinators needed in worlds crop production
Environmental reasons for maintaining biodiversity?
- forests and peat bogs absorb carbon dioxide
- recycling elements like C, N, S and P
- microorganisms break down organic waste material
- transpiration from plants in water cycle
Moral, ethical + aesthetic reasons for maintaining biodiversity?
- share planet with a huge range of other organisms and we have no right to drive them to extinction
- humans = custody of the Earth so we should value and protect the organisms that share it with us
- people gain pleasure from biodiversity, in being in the natural world
- inspiration for artists, photographers, poets, writers
Pros and cons of national parks?
PROS: human access is controlled, industrial activities regulated, hunting is limited/prohibited, control invasive species, research and restoration, bigger environment, more space, resources, allows for migration, reduces the edge effects, can have habitat/wildlife corridor
CONS: requires active management
Pros and cons of zoos?
PROS: scientific research of genetics, behaviours and habitat needs, education for public, protection, assissted reproduction/embryo transfer w/ surrogates, captive breeding programs (allows for increase in population, and then can be reintroduced into the wild)
CONS: reduces genetic diversity through inbreeding, some species do not breed in captivity, not always adequate habitats, can be hard to reintegrate into the natural world due to lacking those skills like hunting, mating, to be most effective need a large number of a species for the highest allele frequency possible
Pros and cons of seed banks?
PROS: if a plant becomes extinct in the wild, can be regrown = maintains biodiversity, keeps a high allele frequency/gene pool because there are samples from different places of the same species, can be stored anywhere in the world irrespective of climate, less vulnerable to disease, protected from changing climate
CONS: not all seeds can be stored because they cannot all be dehydrated to 5% water (coffee + cocoa), and can only be stored for a short time, viability needs to be tested every 5 years by growing them (bad for small samples), need to be stored at -18 and underground, collection can be expensive if in remote areas
How can biodiversity be measured?
- species diversity (richness and eveness)
- genetic diversity
- ecosystem diversity
What is the role of a foundation species?
creating and enhancing the environement to benefit other species e.g. elephants breaking up trees to make space for grasses
What is a native species?
live and thrive in that particular ecosystem
What does a keystone species do?
role has an effect on types or abundance of other species e.g. predators and pollinators
What is the role of an indicator species?
early warnings of damage to an ecosystem - measure habitat/ecosystem quality
* Amphibians being so sensitive to environmental change, good indicator if the environment is of quality or not
What is a non-native species, and what risk do they have?
migrated into an ecosystem; risk is that they could cause environmental, human or economic harm, could outcompete the native and endanger them, decrease diversity of native species, destroy aesthetics of habitat
What is the competitive exclusion principle?
No two species can occupy the same niche for an extended period of time. One will outcompete the other.
Example of keystone species effect?
Purple Sea Star
* no sea star = mussels took over, no other species could live there
* predator of the mussels was gone
What does a higher species diversity mean?
species more stable = resist enviornmental changes = reduces risk of extinction
How can you combat alien species?
- physical removal -> cane toad cullings
- biological predator
What is an alien species?
a species which does not originate from that place, and is there by humans or migration
How might an alien species disrupt ecosystem?
- competition
- foodweb changes
- alters predator/prey relationship could decrease one species
- no natural predator of the alien species
- lowered diversity
How might an alien species disrupt ecosystem?
- competition
- foodweb changes
- alters predator/prey relationship could decrease one species
- no natural predator of the alien species
- lowered diversity
Example of alien species going out of control
The cane toad was brought to Australia to control the cane beetle which was destroying the sugar cane crop. But, the cane toad ate anything, can move incredibly quickly and can reproduce at high rates.
Why might a species become extinct?
- very small population, means genetic drift has a greater impact, leading to a greater decrease in genetic variation
- increased inbreeding
- decrease genetic variation
- decreased fitness
What is conservation?
the action of preserving, protecting or guarding in order to maintain biodiversity.
What is the difference between in-situ and ex-situ?
in-situ - conservation in the species own habitat, in site
ex-situ - conservation in another place to the species own habitat, off site
Give 3 examples of ex-situ and in-situ conservation.
Ex-situ: botanical gardens, seed banks, zoos
In-situ: national parks, marine parks, nature reserves
What does CITES do?
controls the trade of endangered animals and any products of them e.g. elephants and their ivory tusks
Give an example of a nature reserve.
Kruger National Park, Yorkshire Dales, Yellowstone
How do CITES classify endangered species ?
By 3 appendices.
Appendix I = most endangered, trade is banned
Appendix II = not endangered but will be if trade continues; can only trade with a permit
Appendix III = species in this group are there because countries that struggle to stop the illegal trade of them need extra support from CITES; can only trade with a permit, and this is easier to obtain than Appendix II
What is the drawback to CITES?
If trade is banned, the value of the product increases, so the breaking the law seems more worthwhile. Also, if a species is announced to be put on the CITES list in adavance, trade increases during that period, to when it is offically illegal.
What does the IUCN do?
assesses the conservation status of an animal or plant
What is the IUCN’s classification system?
of the assessed specices, that have sufficient data: extinct, extinct in the wild, threatened (critically endangered, endangered or vulnerable), near threatened or least concern.
What do conserved areas do?
- human access is strictly controlled
- industrial activities regulated
- hunting limited/prohibited
What are the roles of botanical gardens?
- protect endangered plant species from competition, weather extremes, eutrophication
- research methods of reproduction and growrth, as well as how to reintroduce plants into new habitats if their natural one has been lost
- education
- tourism/aesthetic pleasure
- reintroduce species into habitats where they have becomes rare/extinct
- create the perfect environment for all/any species to grow
What is a seed bank? Give an example.
a facility where seeds are dried and kept in cold storage to conserve plant biodiversity.
Example: Svalbard, International Rice Institute
Features of domain bacteria?
- Prokaryotic
- DNA is circular, no histone proteins
- plasmids
- 70S ribsomes
- no membrane bound organelles
- cell walls of peptidoglycan
- binary fission
- single cells, or small groups of cells
Features of domain archaea?
- no nucleus = DNA is circular chromosome with histone proteins
- plasmids
- no membrance bound organelles
- 70S ribsomes, but despite being smaller, have more in common with eukaryotic ribosomes
- cell walls but NOT peptidoglycan
- binary fission
- single cells or small groups of cells
- membrane lipids are unqiue
Features off domain eukarya?
- has a nucleus
- membrane bound organelles
- linear DNA with histone proteins
- 80S ribsomes (mitochondria and chloroplasts have 70S ribosomes)
- unicellular, colonial or multicellular
- mitosis
- cell walls in some (plants)
- asexual and sexual reproduction
- chloroplasts and mitochondria DNA is circular
What is the difference between archaea and bacteria?
- archaea has histone proteins and bacteria do not
- bacteria has circular DNA, archaea have ‘circular’ chromosome
- the 70S ribosomes in archaea are more similar to a eukaryote
- cell walls are not peptidoglycan in archaea
- archaea have unique membrane lipids
