Biodiversity 1-2 Flashcards
Define biophilia
the human bond with other species
Name the 4 different ecosystem services
- direct use value
- indirect use value
- optional value
- existence value
What is Edward O Wilson’s definition of biodiversity?
- the variety of organisms considered at all levels, from genetic variants belonging to the same through arrays of species to arrays of genera families an higher taxonomic levels including the variety of ecosystems which compromise both communities of organisms within particular conditions where they live
Define genetic diversity
heritable variation tht is observed within and between populations of organisms
Where are genes found?
In the nuclei of all cells of all organisms
What are genes made up of?
made up of DNA situated along chromosomes
How is new genetic variation created?
by gene and chromosomes mutations and recombination in sexually reproducing organisms
What are the benefits of genetic variation?
it enables evolution and adaptation of species within a changing environment and is essential for the long-term survival
What is the problem with low genetic diversity?
it may mean that a species is unable to adapt to changing conditions in the future
Define a biome
major regional groupings of plants and animals discernible at a global scale (major ecosystem)
What factors correlate with terrestrial biome distribution?
- precipitation
- elevation
- temperature
- latitude
Name the 8 major biomes
- tundra
- taiga
- temperate forest
- grassland
- chaparral
- desert
- tropical forest
- aquatic biomes
Name some changes to food production since the green revolution in 1960
- food production has doubled
- and per capita grown significantly
- food price has fallen
What is the Cambrian period?
The geological timescale when species were first evolving and mass biodiversity diversification began
Name and explain the three stages in changes in number of species
1) radiation where species of diversifying
2) stabilisation where populations tend to level out and sustain themselves
3) extinction where populations and species get completely wiped out
What are some catastrophic environmental factors leading to extinctions of species?
meteor strike
continental drift
changing climate
ocean anoxia
What is the clatharate gun hypothesis?
rises in sea temperatures which trigger the sudden release from methane clathrate compounds as well as permafrost most volatile greenhouse gases
describe the 6th extinction?
the anthropogenic extinction where humans have started to have an impact on biodiversity and the number of species for the first time in the late holocene
What does extinction debt mean?
where the population level is so low that there is no way the species can reproduce successfully even if there are a few individuals left
How has habitat change become an increased issue recently?
- intensive, non sustainable agriculture, mining, foresty, urbanisation etc
Define a natural habitat
a habitat that remains unmodified by human activities
What is a plagioclimax community
they require systematic regular management in order to maintain their biodiversity interest
Whats the difference between habitat degradation and conversion?
degradation is temporary and only impact some species
Conversion is permanent and impacts most species
Define an invasive species
taxa found outside of their natural distributional range as a result of human interaction and which have become established in natural or semi natural habitats
What are the impacts of invasive species?
They change the habitat and threaten native biodiversity
Name some solutions to invasive species
- public education
- control of movement of alien species
- investment into biological, chemical and physical controls
- better monitoring of actual effects of species
What is over exploitation?
The unsustainable living of humans off the land and seas, doesn’t allow regeneration
What is acid rain?
when co2 dissolves in rainwater forming carbonic acid, as well as sulphur and nitrous oxides form sulphur and nitric acids with rainwater
Define eutrophication
the enrichment of an ecosystem with chemical nutrients, typically compounds containing nitrogen, phosphorus or both
Name some solutions to eutrophication
- legislative changes in order for emissions to decrease
- alternative power sources
What are r selected species?
those with short life spans and high reproductive rates that predominate in unstable environment
Name the 4 factors which threaten existence of a species
- small population
- fragmented population
- habitat specific
- poor adaptation to niche
