BISV - IB Biology - Topic 5 - Ecology and Evolution

Terms in this set (36)

Arguments for Action
◾Risks of inaction are potentially severe, including increased frequency of severe weather conditions (e.g. droughts, floods) and rising sea levels
◾Higher temperatures will increase the spread of vector-borne diseases
◾Loss of habitat will result in the extinction of some species, resulting in a loss of biodiversity
◾Changes in global temperature may affect food production, resulting in famine in certain regions
◾The effects of increased temperatures (e.g. rising sea levels) could destroy certain industries which countries rely on, leading to poverty
◾All of these consequences could place a far greater economic burden on countries than if action were taken now
◾These factors would increase competition for available resources, potentially leading to increased international tensions
Arguments for Inaction
◾Cutting greenhouse emissions may delay economic growth in developing countries, increasing poverty in these regions
◾Very difficult to police - what level of action would be considered sufficient on a global scale in the current absence of scientific consensus?
◾Boycotting trade with non-compliant countries could negatively effect economies and create international tensions
◾No guarantee that human intervention will be sufficient to alter global climate patterns
◾Money and industrial practices that may be used to develop future technologies may be lost due to restrictions imposed by carbon reduction schemes
◾Carbon reduction schemes will likely result in significant job losses from key industries, retraining workers will require significant time and money
Fossil Record - Bones and shells etc found which show structures of organisms have changed over time (evolution) and that many species are now extinct. Fossils always found in a consistent order which in rocks of particular ages. Suggests ancestral species gave rise to modern species. Show intermediate stages in development.
Selective breeding of domesticated animals is an example of artificial selection, which occurs when man directly intervenes in the breeding of animals to produce desired traits in offspring
As a result of many generations of selective breeding, domesticated breeds can show significant variation compared to the wild counterparts, demonstrating evolutionary changes in a much shorter time frame than might have occurred naturally
Comparative anatomy of groups of animals or plants shows certain
structural features are basically similar; homologous structures are those that are similar in shape in different types
of organisms; structural similarities imply a common ancestry;
(homologous structures) used in different ways; example is pentadactyl limb in vertebrates / modification of ovary wall or
pericarp to aid seed dispersal / other suitable example; adapted to different mode of locomotion in particular environment / example of two differences such as bat's wing and human hand; illustrates adaptive radiation since basic plan adapted to different niches; the more exclusive the shared homologies the closer two organisms are related; certain homologous structures in some species with no apparent function such as human appendix (homologous with functional appendix in herbivores);