Blueprint of life- dot point 1
Environmental Change
Evolution is the process of change that occurs in living organisms over many generations. It is the result of natural selection by the environment of favourable variations in the organisms.
Changes in the environment of living organisms can lead to the evolution of plant and animal species. These environmental changes in condition may be physical- temperature, rainfall, sea level and landforms e.g. Peppered Moths chemical- water salinity, acidity, use of pesticides, oxygen levels e.g. DDT mosquitoes competition for resources - food, water, shelter and mates e.g. dinosaurs and mammals
Evidence for evolution
Palaeontology- study of fossils
Fossil record of organisms illustrates a clear change from simple to very complex organisms. They provides evidence that living organisms have changed over time.
E.g. early horses were much smaller.
Transitional forms are organisms that indicate the development of one group of organisms from another or from a common ancestor. Helps understand how evolutionary change has occurred. E.g. Archaeopteryx was a flying dinosaur with both reptile teeth, claws and bird feathers
Biogeography- study of the distribution of living things
Particular types of plants and animals are found in certain continents and not others. By looking at the pattern of distribution of an organism today, plus its fossil distribution in the past, we are can reconstruct evolutionary history.
E.g. emus are koalas are unique to Australia, turkeys are unique to North America
Comparative embryology- study of embryos of different organisms looking for similarities
The similarity between the embryos of different vertebrate species suggests a common ancestry. E.g. many embryo vertebrates have gill pouches
Comparative anatomy- study of structure similarities in organisms
The bone structures they have in common are evidence of similar inherited characteristics from common ancestors. E.g.
Evolution is the process of change that occurs in living organisms over many generations. It is the result of natural selection by the environment of favourable variations in the organisms.
Changes in the environment of living organisms can lead to the evolution of plant and animal species. These environmental changes in condition may be physical- temperature, rainfall, sea level and landforms e.g. Peppered Moths chemical- water salinity, acidity, use of pesticides, oxygen levels e.g. DDT mosquitoes competition for resources - food, water, shelter and mates e.g. dinosaurs and mammals
Evidence for evolution
Palaeontology- study of fossils
Fossil record of organisms illustrates a clear change from simple to very complex organisms. They provides evidence that living organisms have changed over time.
E.g. early horses were much smaller.
Transitional forms are organisms that indicate the development of one group of organisms from another or from a common ancestor. Helps understand how evolutionary change has occurred. E.g. Archaeopteryx was a flying dinosaur with both reptile teeth, claws and bird feathers
Biogeography- study of the distribution of living things
Particular types of plants and animals are found in certain continents and not others. By looking at the pattern of distribution of an organism today, plus its fossil distribution in the past, we are can reconstruct evolutionary history.
E.g. emus are koalas are unique to Australia, turkeys are unique to North America
Comparative embryology- study of embryos of different organisms looking for similarities
The similarity between the embryos of different vertebrate species suggests a common ancestry. E.g. many embryo vertebrates have gill pouches
Comparative anatomy- study of structure similarities in organisms
The bone structures they have in common are evidence of similar inherited characteristics from common ancestors. E.g.