Download Adaptation and Speciation

Speciation and Adaptation
Warm-up Questions:
• Some organisms have genes that improve their ability
to survive and reproduce. If the genes also help their
offspring survive and reproduce, then which of the
following will most likely increase?
•
•
•
•
a.
b.
c.
d.
The frequency of the genes in one individual
The frequency of the genes in the population
The number of genes in one chromosome
The number of genes in the species
• Identify the type of selection displayed in the graph
below:
Stabilizing
Inherited Variation:
 Variation in a characteristic that is a result of
genetic inheritance.
 Essential for natural selection to result in a new
species.
Advantageous Adaptation:
 An adaptation that is beneficial to the organism
(physical adaptations, or even changes in breeding
to produce when food is most heavily available.).
Adapted for an
environment with
bright light.
Fitness:
 In evolutionary terms, fitness is the an organism’s
reproductive success in surviving and producing
viable offspring.
Genetic Resistance to Pesticides:
 When a species (insects) has a genetic mutation
that makes them less susceptible to the effects of
pesticides allowing them to live on after one is
applied.
Speciation:
 The formation of new and distinct species in the
course of evolution.
 The start of a new population elsewhere often
provides the best opportunity for speciation to
occur.
Recombination:
 Process by which pieces of DNA are broken and
recombined to produce new combinations of
alleles.
 This recombination process creates genetic
diversity at the level of genes that reflects
differences in the DNA sequences of different
organisms.
Gene Frequency:
 The ratio of a particular allele to the total of all
other alleles of the same gene in a given
population.
Differential Reproductive Success:
 The difference between individuals in a given
generation and how many offspring they are able
to leave.
 The more successful the adaptions, the more likely
an organism is to have a greater amount of offspring.
 To improve success, some species produce more
babies than will survive in order to maintain a
steady population.
Mimicry:
 Mimicry is a similarity of one species to another
that protects one or both.
 Example: A scarlet king snake, though harmless,
mimics the pattern if the venomous coral snake in
order to deter predators.
Venomous
Non-venomous