Competiton And Enviromental Change Flashcards
Organisms compete for……
And what are they?
Resources to survive. Organisms need things from their environment and from other organisms in order to survive and reproduce.
Plants need light, space, water and minerals (nutrients) from the soil
Animals news space (territory), food , water and mates.
What occurs if organisms compete with each other (and members of their own species) for the same recourses.
E.g red and grey squirrels live in the same habitat and eat the same food. Competition with grey squirrels for these resources means there is not enough for the Reds. So the red squirrel population is decreasing as the grey squirrels are more adapted and powerful
Environmental changes are called by different factors, what are they? (2)
Living factors and non-living factors.
State 4 living factors that causes environmental change in which animals and plants live in.
1- a change in the occurrence of infectious diseases
2- a change in the number of predators
3- a change in the number of prey or availability of food sources
4- a change in the number or types of competitors
State 3 non-living factors that causes change in the environment what plants and animals live in.
1- a change in average temperature
2- a change in average rainfall
3- a change in the level of air or water pollution.
What are the 3 ways environmental changes affect populations.
1- population size increases.
2-population size decreases
3- population distribution changes
How does the increase in population size affect populations? In animals and plants
E.g number of prey increases so theirs more food for predators. So more predators survive and reproduce as their numbers increase too.
How does population size decrease affect population of plants or animals?(3)
E.g the number of bee’s in theUS is falling rapidly. Experts aren’t sure why but they think it could be because;
1- some pesticides may be having a negative effect on bee’s
2- there’s less food available - there aren’t as ,any nectar rich plants around anymore.
3- there’s more diseases - bee’s are being killed by new pathogens and parasites.
How does population distribution changes affect populations of plants and animals?
A change in distribution means a change in where an organism lives. For example the distribution of bird species in Germany is changing because of the rise in average temperature, e.g the European bee-eater bird is a Mediterranean species but now its present in parts of Germany.
