Evolution Flashcards
What is the main difference between Lamarck’s theory of evolution and Darwin’s theory?
Lamarck suggested that characteristics which developed during the lifetime of the organism could be passed on. Darwin said that organisms with the best characteristics survived to breed and the offspring inherited the characteristic.
What is meant by ‘evolution’?
The idea that organisms have developed from simple life forms and have changed (evolved) over time.
Why did it take so long for Darwin’s theory to be accepted?
Scientists didn’t have enough evidence and they didn’t know about genes, Some people believed that God made all the animals and plants to look as they did.
Why is it that only some members of a population survive to breed?
Organisms compete for things such as food or light. If an organism is well adapted to its environment it will survive. Poorly adapted ones die before they breed.
Why is there variation between members of the same species?
If the offspring are produced by sexual reproduction, then the genes of the offspring of both parents are inherited in different combinations when gametes fuse.
What is meant by the term ‘survival of the fittest’?
Those that are best adapted or suited to their environment live long enough to breed. the weaker ones may die before they breed.
What is meant by ‘natural selection’?
Organisms which are best adapted to their environment survive, breed and pass on their genes to the next generation.
What is meant by the term ‘species’?
Species are organisms which look very similar to each other abd can interbreed to produce fertile offspring.
Suggest three factors that could change in a habitat, causing problems for the organisms living there.
Three of: the climate may change - it could become hotter, colder, wetter or drier. A new predator may move into the area. A new disease may affect the population . A new competitor for the food supply may move into the area. There may be a loss of habitat such as nesting sites.
Why do biologists draw evolutionary trees?
Evolutionary trees show the relationships between organisms and whether they had common ancestors.
