NATURAL SELECTION & ADAPTIVE BEHAVIOR COLLABORATIVE GENE
Natural Selection – an evolutionary process by which Genetic Code – information that helps us grow from one
those species who can adapt are the ones who will single cell to a person made of trillions cell.
survive and will leave the most fit offspring. Chromosomes – threadlike structures that come in 23
→ The adaptive behaviors and characteristics will pairs, with one member of each pair coming from each
be passed down to the next generation. parent.
Adaptive Behavior – behavior that promotes an organism’s → It can be found in the nucleus of the cell and it
survival in its natural habitat. contains the genetic substance DNA.
DNA – a complex molecule (double helix structure) that
EVOLUTIONARY PSYCHOLOGY
contains genetic information.
Evolutionary Psychology – emphasizes the importance of Genes – units of hereditary information and are short
adaptation, reproduction, and “survival of the fittest” in segment of DNA.
shaping behaviors.
→ These help cells to reproduce themselves and
→ “Fit” refers to the offspring of a species who can manufacture proteins that maintain life.
survive long enough to have their offspring of
Protein – building blocks of the cell and the regulator
their own.
that directs body processes.
→ chance of survival = reproductive success
Human Genome Project – maps out the entire genetic
David Buss – emphasizes that evolution influences not
contents of our cells (linked to certain functions and
only the biological but also the psychological makeup of
developmental outcomes).
human.
→ Gene has its own location in a particular
Evolutionary Developmental Psychology – evolutionary chromosome.
psychology to understand development.
→ Major gene identification and discovery methods
→ Humans require time to develop large brains and are:
understand complexity of human society →
[1] Genome-Wide Association Method – used to
longer childhood period.
identify genetic variations linked to certain
→ Many psychological mechanisms are domain- diseases.
specific – it applies only to a specific aspect of a → Comparing the genes of a person who has a
person’s psychological makeup. certain disease to a person who don’t have
→ Brain is not a general device that can be the same disease.
applied to vast array of problems. [2] Linkage Analysis – to discover the location of
→ It evolved to process information related genes in relation to a marker gene (position of
with recurring problems experienced by our already known).
ancestors (e.g., hunting).
→ Genes passed to offspring tend to be in
→ Since evolutionary selection is primarily tied to close proximity to each other so that genes
reproductive fitness, it has not eliminated any involved in a disease are usually located
harmful conditions & nonadaptive behavior to older near the marker genes.
adults since reproduction mainly happens on the first
[3] Next-Generation Sequencing – a term used to
half of life (Paul Baltes).
describe the vast increase in genetic data
→ Alzheimer’s Disease would have been eliminated
generated at lower cost & shorter period
eons ago since this inhibits successful
compared in the past.
reproduction.
, → Entire human genome can be sequence in a → The presence of Y chromosomes in the 23rd pair
day compared before which is 10 years. determines natal sex of a person (XX in females
[4] Thousand Genome Project – the goal is to and XY in males).
→ The human genetic process creates several important
determine the genomic sequences of at least
sources of variability:
1000 individuals from different ethnic groups.
[1] The chromosomes in the zygote chromosomes in
→ Rather than being a group of independent genes,
the mother’s ovaries/father’s testes. The
human genome consists of many genes that
chromosomes the goes into the gamete are a matter
COLLABORATE both with each other and with
of chance.
nongenetic factors inside & outside of the body.
Identical Twin (Monozygotic) – a single zygote splits
→ Gene Expression – genes can be turned on/off by
into two identical parts, creating two identical
their environment.
persons.
→ Methylation – tiny atoms attached themselves to
Fraternal Twin (Dizygotic) – two eggs are fertilized by
the outside of a gene → more or less capable of
different sperms, creating two persons w/ different
receiving & responding to biochemical signals of
genetic makeup.
body.
[2] Cellular mistake or environmental events can
GENES & CHROMOSOMES produce mutated gene – a permanently altered
segment of DNA.
→ Genes get passed down from generation to
generation (they are enduring) through three Susceptibility Genes – genes that make individual
processes: MORE vulnerable to certain diseases or accelerated
aging.
Mitosis – a cellular reproduction in which the nucleus of a
body cell divides itself into two identical parts. Longevity Genes – genes that make people LESS
vulnerable to certain disease and more likely to live
→ Each containing the same DNA as the parent’s
longer.
cells and arranged in the same chromosomal
pairs. Genotype – a person’s overall genetic materials.
46 chromosomes →
46 chromosomes Phenotype – the way a person’s genotype is expressed in
46 chromosomes
observed and measurable characteristics.
Meiosis – a form of cell division that happens in → Even though two persons are genetically
egg/sperm cells (gametes) in which the cells duplicate its identical, they may still vary in terms of physical
chromosomes and then divides twice. & psychological characteristics.
→ The end results are four cells that contain only
half of the genetic materials (only 23 unpaired GENETIC PRINCIPLES
chromosomes).
Dominant-Recessive Genes – one gene of a pair always
23 chromosomes
exerts its effects (dominant) and overrides the potential
23 chromosomes (23 chromatids)
→ influence of the other genes (recessive).
(46 chromatids) 23 chromosomes
46 chromosomes → (23 chromatids) → Only need one dominant gene to express the
(92 chromatids) 23 chromosomes trait (either from mother of father).
23 chromosomes (23 chromatids)
→ → A recessive gene needs another recessive gene
(46 chromatids) 23 chromosomes
(each one from both parents) to express itself.
(23 chromatids)
Fertilization – a stage in reproduction in which sperm and Sex-Linked Genes – most mutated genes are recessive but
egg cells fuse to create a zygote – a single fertilized egg. when this is carried on the X chromosomes → X-linked
23 chromosomes (sperm) + 23 chromosomes (egg) = 46 chromosomes inheritance.