Marine Science 4.5
Scientists studied a fish species that has individuals of different body sizes (large and small). Fishermen usually catch most of the large fish, while most of the small-bodied fish remain in the population. Scientists observed the next generation of this species and found that the average body size of fish was smaller than in the previous generation. How have human beings influenced the evolution of this fish species?
By over-fishing the big fish, more smaller fish are left behind to reproduce, so their offspring will be smaller as well.
What is the difference between correlation and causality
Correlation indicates that the two numbers are related in some way. Causation requires more proof that there is no lurking variable that creates the relationship.
How can genetic variation affect the size and survival of a population?
Genetic variation can affect the size and survival of a population by having a genetic trait being passed down. These characteristics might help or hurt the organism's chances of survival.
How does a change in an organism, acquired over its lifetime, become heritable?
If an organism changes over its lifetime in order to adapt to its environment, it is better able to survive and pass along its genes to the next generation.
How does parental care help the survival of the blue whale species?
It helps because the mother puts in a lot of time and energy in making sure her baby survives. She makes sure her baby is fed and protected from predators.
Explain what overproduction refers to, in the context of natural selection.
Overproduction of offspring is a driving force in natural selection. All species, even slow reproducers like whales, overproduce in the sense that they have more offspring than can realistically survive based on the resources available.
How does overproduction contribute to the survival of a species?
Overproduction supports survival of the fittest. That means the stronger ones will survive and adapt and pass their genes on to the next generation.
What are the five (5) conditions required for natural selection? (Lesson 04.05, Page 3)
Overproduction, Variation, Heritability Differential Reproduction, Descent With Modification
Variation
The characteristics of organisms within a species must vary. These characteristics might help or hurt the organism's chances of survival.
Descent With Modification
The heritable traits that helped an organism survive have been passed on. Over many generations adaptation could cause a species to evolve.
What is artificial selection?
The intentional breeding of a species for a desired trait
What is genetic variation?
The number of chromosomes and the content of the genetic material vary from species to species.
Differential Reproduction
When some organisms survive and reproduce more than other due to their variations.
Overproduction
organisms produce more offspring than can survive
Heritability
the ability of a trait to be passed down from one generation to the next. If a certain characteristic helps a species survive, it must be passed on genetically in order to have a long-term effect.
