Adaptations

ADAPTATIONS

• Adaptation - a characteristic of an organism that enables it to function more effectively or survive in its surroundings
• 5 Types of Adaptations

1. Structural - related to the structure of the organism (e.g. The streamlined shape of fish enables it to swim more quickly through water.)
2. Colour - related to colour (e.g. camouflage, warning colouration of blue-ringed octopus, mimicry of butterfly wings with 'eye spot')
3. Physiological - related to the organism's metabolism (e.g. During hibernation, bears reduce their chemical processes.)
4. Behavioural - related to behaviour (e.g. During the heat of the day in the desert, lizards burrow into the sand to find a cooler place.)
5. Reproductive - related to courtship, mating or rearing of young (e.g. Peacocks fan their feathers to attract a mate.)

Assignment:

Write your answer to the following terms and questions:

ECOSYSTEMS: ADAPTING TO CHANGE -- OR NOT

"Biodiversity is gradually developed through selective pressures acting on populations to gradually modify and adapt them to various habitats and niches"

Trait: any particular characteristic of physical appearance (both 

      outward appearance and internal anatomy), metabolism, aptitude,   

      or behavior.

   * Physical traits:

   

   * Behavioral traits:

Hereditary (genetic): individuals are born with certain traits that they 

      inherited from their parents.

DNA (Deoxyribonucleic acid):   

Gene:  segment of the DNA that codes for one particular protein

    * each individual has two sets of genes: one from each parent

Alleles:

Gene pool:  the total of all the different alleles of each gene that exist in the entire population of the species.

    * some genes are common and some are rare

Differential reproduction:

Selective pressures: causes some individuals to reproduce and others

        not to.

     * social, economic, cultural, political   

     * acting on the gene pools of all species gradually lead to the 

          development of a balanced ecosystem

     * if conditions do not change - tend to preserve the status quo

Selective breeding:

      * selected traits:

Natural Selection:

      * presented by Charles Darwin in 1859, "The Origin of Species 

           by Natural Selection"

Survival of the fittest: those individual having traits that best enable the individual to cope with the biotic and abiotic factors of their environment survive.

What must an organism do if it is going to survive?

Adaptations

1. Climate or other abiotic factor

2. Obtain food, water, or energy

3. Avoid predation, survive parasitic infections

4. Reproduction - find mates

5. Shelter

6. Disperse

Mutation: a change in the DNA molecule

      * they are random events

      * if they result in death they are called lethal mutations

Competition:

Speciation:  results in two or more species developing from one

      * may occur when populations are physically isolated from one 

          another

If factors change in an ecosystem:

1. Readaptation

2. Migration

3. Extinction

What will determine if a species survives a change?

1. Rate and degree of change

2. Genetic variability in the starting gene pool

3. Biotic potential of the species

4. Size of the organism

5. Geographic distribution

The Forces Behind Climate Changes

Continents are continually on the move toward different relative positions on the earth and climates change accordingly

Continental drift:

Tectonic plates: