Ecology 1 Flashcards
Who coined ecology
Ernst Haeckel in 1870
Explain ecology briefly
- A branch of biology
- Looks at the higher levels of organisation, including the population; community; ecosystem and biosphere
What is the level of organisation order
- Atom
- Molecule
-Organelle - Cell
- Tissue
- Organs
- Individual organism
- Population
- Community
- Ecosystem
- Biosphere
What is ecology
- Interactions among organisms
- Interactions between organisms and their physical environment
- How these interactions influence the distribution and abundance of organisms
Definition of ecology
The scientific study of how the distributions and abundances of populations (and species) are determined by the interactions of individual organisms with their physical and biological environments
What is meant by “ scientific study “
- Explain certain aspect of natural world
- Make observations
- Based on observations construct a falsifiable hypothesis
- Conduct experiemnts to test hypothesis
What is a falsifiable hypothesis
A hypothesis that can be disproved through experimentation
- You can never prove anything directly, only indirectly through falsification
How do we study ecology
- Observation
- observe natural world - Experiments
- test hypotheses using scientific method - Mathematical model
- use equations to describe ecosystems and predict their response to certain situaitions
What is meant by environment
The environment includes both the physical (abiotic) and biological (biotic) environment
What does the physical environment include
- Rocks
- Soil
- Water
- Sunshine
- Minerals
- Pollution
Explain environmental condition
The environment includes both the physical (abiotic) and biological (biotic) environment
eg ) Temperature, salinity, moisture, elevation, depth, nitrogen concentration of water, beach grain size etc etc etc
Explain biological environment
- Includes an organism’s: Food, Parasites, Mates, Offspring, Competitors,
Predators
i.e. All of the other organisms it ever encounters, including its own and other species
What is a resource
- Something that is required or used by an organism, the quantities of which can be reduced by the organism
eg ) Dissolved oxygen, sunlight, water, carbon dioxide, mineral nutrients, organisms as food
What are abiotic factors
- Non-living
- Make up the physical environment
What are biotic factors
- Living or once living, Make up the biological environment
- Abiotic and Biotic factors are not independent; they work hand in hand
Explain levels of diversity fully
- Ecology can be studied at different levels of biological diversity, from lowest to highest
complexity:
- Individual
- Population
- Community
- Ecosystem
- Biome
- Biosphere
Explain the biological species concept
- Individuals are considered to be of the SAME species if they can interbreed to produce viable offspring – they are effectively genetically identical
- ndividuals are considered to be of DIFFERENT species if they either cannot interbreed, or they can interbreed but are unable to produce viable offspring – they are genetically different
What is a population
- A population is a group of individuals of the same species that occupies the same area
- Individuals in the population are capable of interbreeding with each other
- A population is a functional unit that interacts with the environment
What is a community
- A community consists of all the populations of different species that occupy the same area
- The populations interact with one another
What is an ecosystem
The biological community together with its associated abiotic (non-living) environment
Explain biome fully
- Defined by major vegetation type
- Determined by temperature and water
Explain biosphere fully
- The layer on Earth (water, land and air) where all living organisms live
- Includes both living and non-living components
- All the ecosystems together
Explain ecology and evolution
- Ecology is tied to the field of evolution
- Organisms evolve in response to ecological pressures (biotic and abiotic)
- Evolution results in adaptations – traits that help an organism to survive and reproduce in its environment
- Natural selection is the process by which evolution occurs
What is evolution
- Charles Darwin – “The Origin of Species” (1859)
- Changes in the traits of living organisms over generations
Explain natural selection
Evolution by natural selection can be
understood in three points:
- There is variation in the traits of organisms
- There is differential offspring survival so that some individuals leave more surviving offspring than others. The environment SELECTS the survivors …and those that leave the most surviving offspring are those that are best suited to their environment
- There is heritability of traits–Offspring inherit the characteristics that made their parents well-suited to the environment, so they too tend to be well-suited to the environment
