1/16/2018

Animal Behavior

Video 1

Two were fighting, the rest just ignored them

Why were those two fighting and not the other ants?

Video 2

One animal most likely male was getting pushed away most likely for territory or a female.

What was the real reason the walrus was getting pushed away?

What season was it?

Video 3

All the horses were eating except for one who was just standing there, one horse stopped and rolled over, they all go over to the horse that’s laying down

Why did just one horse lay down?

  • Physiological Mechanisms

  • Genetics

  • Development

  • Evolution

Ecology: The scientific study of the interactions among organisms and their environments.

Terms you should remember and know:

  • Individual- A single, separate organism (animal or plant) distinguished from others of a same kind.
  • Population-A group of organisms of one species that interbreed and live in the same place at the same time.
  • Adaption (n) Something produced by adapting.
    • Adapt (v)-The adjustment or changes in behavior, physiology, and structure of an organism to become more suited to an environment.
  • Natural Selection-Heritable traits increase an organism’s chances of survival and reproduction.
  • Genetic Drift- When chance events cause changes in frequencies of alleles in a population.
  • Gene Flow- The movement and exchange of genes or alleles from one population of species to another.
  • Genotype- The genetic constitution of an organism that determines the hereditary potentials and limitations of an individual.
  • Phenotype-The physical characteristic of an organism as a result of the interaction of its genotype and the environment.
  • Phenotypic Plasticity-the ability of one genotype to produce more than one phenotype when exposed to different environments.
  • Allele-Any one of two or more genes that may occur alternatively at a given site on a chromosome.
  • Gene-Segments of DNA located on chromosomes that are inherited from our parents and contain the codes for the production of specific proteins.
  • Fitness-The ability to survive to reproductive age, find a mate, and produce offspring.
  • Divergent Evolution-The process by which a species evolves into two or more descendant or different forms.
  • Convergent Evolution-When organisms that are not closely related independently evolve similar traits as a result of having to adapt to similar environments or ecological niches.

Phenotype = Genotype + ? 

(? is the environment)

Phenotypic Variation in a population is due to both.

Heritability: The portion of the phenotypic variation in a population due to genetic differences between individuals.

Every trait is influenced by both genes and environment

 

Natural Selection = one mechanism of evolution

IF: Three conditions are met

THEN: Adaptive EVOLUTION occurs

  1. Phenotypic Variation in the Population
  2. Some of that variation is ??
  3. Interation with the environment: Traits that increase survival and reproduction of individuals of individuals increase in frequency.
  • Differential survival and reproductive success results from organisms interacting with their environment (Natural Selection).
    • Those individuals with traits best suited for the local environment survive, grow and leave more fertile offspring.
    • This leads to gradual changes in the genetic makeup of a population over the generations. Favorable characteristics accumulate over time.

What changes is the Relative Frequency of Genes (alleles)

  • Natural selection acts on individual
  • Evolution acts on population

The result of natural selection is evolutionary adaption

Why aren’t organisms “perfectly adapted” to their environments?

  • Environments are always changing
  • What is perfection?
  • The organism is not currently in the environment that it evolved in
  • Genetic constraints and lack of genetic variation
  • Gene flow
  • Ecological trade-offs

Is all evolution adaptive evolution?    NO!