Biodiversity and Evolution Flashcards
What is a habitat?
A place where an individual in a species lives. A specific locality with a specific set of condition and and organisms living there.
What is a species?
A group of individual organisms who are very similar in appearance, anatomy, biochemistry, physiology and genetics and who can interbreed to create fertile offspring.
What is biodiversity?
The variety of life - all of the different species in the world, the genes that they contain and the ecosystems of which they are part of.
What are the different levels that biodiversity can be considered on?
- The range of habitats in which species live
- The difference between species as all are different from one another
E.g. structural and functional differences - Genetic variation between individuals within a species
Explain what species 2000 and the Integrated Taxonomic Information system did in 2001.
They attempted to create the Catalogue of life - a comprehensive catalogue of all known species on earth. By 2007, 100, 000,0 species were discovered, estimated just over half of the known species and 10% of all species.
Why and how should you randomise samples?
People are likely to deliberately include more of larger or more colourful species of plat in a sample, which would bias the sampling. Randomly choosing areas to sample solves this and is achievable by:
- Taking samples at regular distances
- Using random numbers to plot random coordinates
- Selecting points from a map and using GPS to find the exact spot
What are quadrats ad how are they used?
They are a square frame used to define the size of a sample area, often 1M square. They are placed on previously randomly selected coordinates.
How is abundance measured in a quadrat?
- Abundance scale, E.g. ACFOR scale where you apply an abundance
scale to each species - Estimate percentage cover by using a grid of strings with 100
squares - Use a point frame - a frame holding many needles/pointers. Species are recorded when touching a pinter.
How is a transect used?
A transect is a line across a habitat, you record species touching the line at intervals, or use a quadrat at each interval (ancontinuous belt transect.
How i sweep netting used when sampling animals.
Walk through a habitat taking large sweeping arcs with a net around the vegetation or water, then emptying and recording the different species (after identifying them). Ensure that none escape - could use a pooter.
How can a sample be collected from trees?
A white sheet can be spread out below a branch that can be nocked with another branch so animals fall off and can be identified and recorded.
What is a pitfall trap and how is it used?
- A small container is set in the soil to catch small animals and containing a little water or scrunched up paper to stop the insects from getting out. An animal moving past it will fall in for later observation. MUST be sheltered from rain to stop i filling up with water.
How does a Tullgren funnel work?
It is a funnel for looking at animals in leaf litter. The leaf litter is placed on the funnel, and a light draws animals downwards as the litter dries. they fall through a mesh screen and into a jar.
How does a light trap work?
UV light attracts insects at night. Under the light, a collecting vessel contains alcohol, and moths and insects fall into the alcohol.
Why do we need to study and sample a habitat?
- Human activity affects the environment in many different ways
- We need to study the environment to understand this effect
- EIA estimate the effects of planned development
