Unit 3 evolution and natural selection Flashcards
what is evolution
how plants and animals have adapted to survive in their environment over many years including how they look and behave
who is associated with the discovery of evolution
charles darwin
what is natural selection
individuals who survive and adapt better to their environment because of their dna mutations are able to reproduce while others who don’t die out
what is adaption
a characteristic that helps an organism to survive in their habitat
what did charles darwin realise about the finchs
different finch’s have different beams depending on the food available to them
what is the process of evolution and natural selection
there is a varation in species due to mutations in DNA
1. far too many young are produced so there is competition for resources
meaning only the individuals best fit to their environment get them and survive (surrival of the fittest) while others end up extrick.
3. those who survived pass on their DNA & reproduce
4. over milions of years and this may lead to new species
examples of environmental changes
seasons, daylight, tides, temperature, trees lose leaves
why do deciduous tree lose their leaves in winter
-to survive, trees have to do photosynthesis which uses chloroplasts which has enzymes in to sped up the reaction.
-but in winter, because it is colder the enzymes don’t work as well
-so trees drop their leaves and hibernate after taking in all the glucose and energy
how do animals adapt to environment changes (seasonal)
-hibernation
-migration
-camaflage
-storing food and preparing for winter
examples of man-made environmental changes
-global warming, fossil fuels=acid rain, extreme weather
-plastic in environments
-light pollution
-zoos and pets
-deforestation
as the human population has increased..
we have increasingly changed the natural environment
how do man-made changes affect living organisms
their distribution and behaviour, new examples of evolution because of the new pressure