Energy Flow & The 10% Rule
While 10% of energy moves up to the next trophic level, the remaining 90% is primarily lost to the environment in this form.
What is heat?
This level of organization is defined as a group of individuals belonging to the same species that live in the same area.
What is a population?
A cactus wren gains a safe place to nest within a cholla cactus, while the cactus remains completely unaffected by the bird's presence.
What is commensalism?
This ecological disruption occurs when human-made structures, like highways, divide a large nature preserve into smaller, isolated sections.
What is habitat fragmentation?
In an ecology experiment, this is the group that is kept under "normal" conditions and used as a standard for comparison.
What is a control group?
In a prairie food web, organisms like carrots, grasses, and grains are defined by this term because they produce their own food via photosynthesis.
What are autotrophs (or producers)?
This specific type of growth occurs when resources are unlimited, resulting in a "J-shaped" curve where the population size increases faster and faster over time.
What is exponential growth?
This interaction occurs when invasive honeysuckle releases toxins into the soil to prevent native plants from growing in the same space.
What is (interspecific) competition?
Because of this process, top-level predators often suffer the most from pollution, as toxins become more concentrated as they move up the food chain.
What is biomagnification?
If a biologist is testing how different temperatures affect seed germination, "temperature" is this specific type of variable.
What is the independent variable?
If a primary consumer in your prairie food web has 450 units of available energy, this is the exact amount of energy a secondary consumer would actually receive.
What is 45 units?
While disease is a density-dependent factor, a severe drought that kills plants regardless of how many are in an area is an example of this type of limiting factor.
What is a density-independent limiting factor?
Non-native pigs and rats in Hawaii engage in this behavior when they eat the flowers of the Loulu tree, preventing it from reproducing.
What is herbivory (or predation)?
These "hitchhiker" species, like the Emerald Ash Borer or Zebra Mussels, often outcompete native species because they lack natural predators.
What are invasive species?
When looking at a population graph, this is the most likely reason a line would suddenly plummet toward zero after years of stability.
What is a limiting factor (or catastrophic event)?
In a food web, this specific term describes an organism like the "Blue Crab" that must consume other organisms to obtain its energy.
What is a heterotroph (or consumer)?
On a logistic growth graph, this term represents the horizontal line where the population size stabilizes because the environment cannot support any more individuals.
What is carrying capacity?
This relationship is defined by an organism, like a tapeworm, living inside a host's intestines and stealing its nutrients.
What is parasitism?
This term refers to the variety of different species in an area; it is the first thing to decline when an ecosystem is stressed by pollution.
What is biodiversity?
This is the factor in an experiment that is measured or observed; it "depends" on the changes made by the researcher.
What is the dependent variable?
Because of the dramatic loss of energy at each level, this is the primary reason why most ecosystems are limited to only 4 or 5 trophic levels.
What is there is not enough energy to support more levels?
If a graph shows a mouse population sharply decreasing over a three-year period, it can be inferred that this specific rate has become higher than the birth rate.
What is the death rate?
In a prairie food web, this is the ecological role of the stink bug because it feeds specifically on the eggs and larvae of the Monarch butterfly.
What is a predator (or secondary consumer)?
Scientists often build these "green" bridges over highways to reconnect split habitats and allow animals to find mates and food safely.
What are wildlife corridors?
To make sure their results aren't just a lucky guess, honors students know they must use a large one of these to ensure their data is reliable .
What is a sample size?