Download Misconceptions relating to Ecology

Misconceptions relating to Ecology
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Food webs are interpreted as a simple food chain
Organisms higher in a food web eat everything that is lower in the food web
The top of the food chain has the most energy as it accumulates up the chain
Populations higher on a food web increase in numbers, because they deplete those
lower in the web
Varying the population of an organism will only affect the others that are directly
connected through a food chain
In a food web, a change in size in one population will only affect another population
if the two populations are directly related as predator and prey
Food chains involve predator and prey, but not producers
The need and roles of a species are general and typical of species
Species coexist in an ecological system because of their compatible needs and
behaviours: they “get along.”
Some ecosystems are limit-less resources and provide an opportunity for limit-less
growth of a population. Populations will increase indefinitely due to limit-less
resources or will increase until the limits are reached at which point the population
will crash and the organisms become extinct
Varying the population of an organism will affect all other organisms to the same
degree. Varying the population of an organism may not affect an ecosystem, because
some organisms are not important
Ecosystems are not a functioning whole, but simply a collection of organisms.
Imbalance of species within its local environment or community is always bad.
An organism cannot change trophic levels
If a population in a food web is disturbed, there will be little or no effect on
populations that are not within the linear sequence in the food web
More herbivores than carnivores because people keep and breed herbivores
Plants do not live in water
Energy is not conserved
Decomposers release some energy that is cycled back to plants
The nitrogen cycle is used to provide energy for the carbon cycle
Energy is not lost in trophic transfer
Carnivores have more energy or power than herbivores do
Plants are dependent on humans, not vice versa
Carbon dioxide is a source of energy for plants
Total biomass for a trophic level is greatest at the top of the food web because the
organisms are larger
The carbon cycle consists of photosynthesis and respiration
Humans provide food for other organisms
Stronger organisms have more energy
Bacteria are the source of energy in a food chain
Plants cannot defend themselves against herbivores
Plants cannot defend themselves against pathogens
Most insect herbivores will eat a variety of plant species
Except for plant toxins, the quality of food for herbivores is the same as that for
carnivores
Density- dependent factors are biotic and density –independent factors are abiotic
Population is an area where living things occur. Population is the number of
people/organisms
The relative sizes of prey and predator populations have no bearing on the size of the
other
Some ecosystems are limitless resources and provide an opportunity for limitless
growth of a population
There are more herbivores than carnivores because people keep and breed herbivores
All factors are limiting except the most abundant one. The most limiting factor is the
least abundant one
The needs and roles of a species are general and typical of species
Traits are passed on by the bigger, stronger organisms that replace the smaller,
weaker ones
There are more herbivores than carnivores because they have more offspring
Carnivores have more energy or power than herbivores do
Soil decreases in fertility over time
Soil is fertile only if humans intervene
The climax community is usually the final stage, long lasting and self-perpetuating
Succession involves separate stages leading ultimately to a deterministic climax
At succession progress, community is characterised by bigger plants and bigger
animals
Communities change little over time
The number of producers is high to satisfy consumers
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“Balance of Nature” refers to populations of predators and prey being smaller in size
Carnivores are big and/or ferocious. Herbivores are passive and/or smaller
The relative sizes of prey and predator populations have no bearing on the size of the
other
Each plant or animal is independent and therefore has no effect on or relationship to
other organisms