Biogeography Flashcards
what is biogeography?
study of the distribution of species and ecosystems in geographic space and through geological time
what are ‘species’?
organism groups that are clearly identified by their appearance structure, physiology and behaviour and can breed
(except mules that are horse and donkey offsprings that cannot breed due to chromosomes)
what are the taxonomic groups?
Kingdom Phylum (or division) Class Order Family Genus Species
the difference between ecological biogeography and historical biogeography?
Ecological biogeography is concerned with short term periods of time, scale, local habitats, species and subspecies e.g why more species in the tropics?
Historical biogeography is concerned with long-term scale, evolutionary periods, global areas, higher taxa, even extinct species e.g why a taxon is endemic?
why early biogeography focuses more on animals than plants?
plants:
are static, easily influenced by the environment
easy to collect the sampled of plants
fossil remains are rarer and harder to inspect
most info from the flower crown which is rarily find
The discovery of Charles Darwin
in 1831 Darwin noticed three different mockingbirds in South Africa, on three Galapagos islands, different tortoises, finch bird sizes, and their beaks and thought of natural selection idea:
1) offsprings vary slightly
2) some characteristics are better suited for the environment
3) offspring with favourable aspects tend to survive better than their relatives
4) survivors will mate and pass on favourable aspects until the environment changes again
what is continental drift
in 1912 german meteorologist Alfred Wegener presented a theory of continental drift according to plant Glossopteris deposit in Africa, Australia, S.America, Antarctica and India. The theory that all continents were one a Pangea. Was accpeted only in 1960s because people thought plants could be dispersed by wind
what is vicariance?
geographical separation of a population, typically a physical barrier like mountains, resulting in a pair of closely related species.
what is a guild
group of animals not related that use the same resources or overlap in their environment requirements
what is climax vegetation?
vegetation assemblage that develops through different stages governed by climate. Nature can be altered by chance also.
what is ecopysiology
science that examines how plants and animals vary in their physiological proceses in response to the the environment
natural theory of biodiversity
arrival of species is stochastic or randomly determined and dispersal is caused by chance
artic poppy
found in alpine zones of Europe, N America, Asia. Is covered by thick hairs to trap heat and has slight toxicity to fight animals. Cup shaped petals trap air which warms up and attracts pollinators. Is heliotropic - turns head towards the sun . 10 degrees warmer in the petals.
desert superbloom
rare heavy rainfall in desert cause flowers to bloom. They lay dormant or sleeping and the seeds are protected by wax for years until water reaches them. These flowers are xerophytes which can survive in droughts.
different kinds of species
subspecies - stable but have diff distributions
polytypic species - that exist as a series of subspecific forms
monotypic species - less variable species that exist only in one form
e.g Herring gull and Greenish warbler
limits of distributions
1 physical - mountains, rivers, deserts, oceans but goose can cross himalayas
2 climatic - frost kills cells, drought desiccates water
3 geological - soil chemistry and structure, pH
4 nature of the habitat - forest in grassland, wetland in forest, usually human land.
5 biological barrier - predation, parasitism, disease, competition, fragmentation
6 historical - mass or ice movements
7 chance - stochastic or randomly determined e.g gust of wind
what is a niche
the demands that an organism places on its environment in terms of physical and chemical conditions, space and food supply
what is the difference between fundamental and realized niche?
fundamental - all niche requirements under ideal conditions with no competition and other species
realized - when other niches overlap and resources become limited
