Lecture 3 Flashcards
Evolutionary Developmental Science
What is theory of scope?
- Nothing in biology makes sense except in the light of evolution- Dobzhansky
- Does not explain the origins of life
What is Evolution?
- A theory that explains the diversity and function of all living things
What does Lamarckianism mean?
Lamarckianism: Inherit traits that change during lifespan
Who was Charles Darwin?
- Famous for his theories in evolution
- Interested in explaining a wide variety of life forms that existed
- Invented theories of natural and sexual selection
What are the Five Components of Darwin’s Evolution by Natural Selection?
- More offspring are born than survive to reproduce
- Individual vary on different traits
- Certain traits are more likely to pass on offspring (via genes)
- Offspring likely inherit those traits
- Environmental conditions have changed, leading to new species
What is the meaning of life biologically?
- It is simply to pass on one’s genes to future generations
What are some Evolutionary misconceptions?
- Survival of the fittest – fitness in biology means # offspring; evolution is really survival of those who produce the most successful lineages
- Group selection – evolution acts at the level of the individual, not the species
- Evolution progresses from simple to complex life forms
Fit vs. Unfit
- More resources are needed to maintain “ultra healthy” offspring who may only produce two offspring
- For those who don’t live fit lifestyles may produce more than 2 offspring as they require less resources to maintain their lifestyle
Group vs. Individual
Groups
- Those who protect “groups” are willing to risk their lives at old age to help the offspring
Individual
- Those who only protect themselves are willing to let the healthy and beneficial die in order to save their own lives
What are higher and lower organisms?
- Evolution: moves toward complex forms of life and is random
- 1 in 4 animal species are beetles
What do Tooby & Cosmides say about Evolutionary Psychology?
- Domain specific mechanisms
- That are at least partly inheritable, solved problems in the E.E.A. (the past evolutionary environment)
- Note that this allows for experience, nurture, and culture to influence the cognitive mechanisms
What are critiques of Evolutionary Psychology?
- Doesn’t typically reveal specific cognitive mechanisms; it’s more of a guide than a manual
- Depends on accurate guesses based on limited information about E.E.A.
- Ignores human culture and other environmental factors
What are two Evolutionary Pitfalls?
- Deterministic Fallacy - if evolved, or in our genes it can’t be changed
- Naturalistic Fallacy- evolved, comes from nature, must be morally good/ acceptable
What are genes and how do they interplay with our environment and heredity?
- Heredity and environment influence individuals’ characteristics
- When scientists first began to investigate the contributions of heredity and environment, they generally emphasized one factor or the other as the prime influence – both matter
- Model of Interaction
What is Genotype?
Genotype: The genetic material an individual inherits
What is Phenotype?
Phenotype: The observable expression of the genotype, including body characteristics and behaviour
What is Environment?
Environment: Includes every aspect of the individual, and his or her surroundings, other than genes
What are the fundamentals of genetic with our parents?
- Parents’ genetic contribute to the child’s genotype
- Contributions of the child’s genotype to his or her own phenotype
- Genetic material is passed on as chromosomes (long, threadlike molecules made up of DNA)
- Known as (deoxyribonucleic acid)
What are Endophenotypes?
Endophenotypes: mediate the pathways between genes and behaviour
What are Regulator genes?
Regulator genes: genes that control activity of other genes
What is Polygenic inheritance?
Polygenic inheritance: inheritance , governs traits with more than one gene
Contribution of the child’s environment to his or her own phenotype
What does norm of reaction mean?
Norm of reaction: all the phenotypes that can theoretically result from a given genotype in relation to environments which it can survive and develop
What is Behavioural genetics?
Behaviour genetics: science concerned with how variation in behaviour and development results from the combination of genetic and environmental factors
Genotypes have what percentage on humans?
- Genes have chromosomes that code for a particular protein sequence that affect other genes
- 2% of human genomes
What the Mechanisms that Contribute to Genetic Diversity?
Mutations: Changes in sections of DNA caused by random or environmental factors
Random assortment: The shuffling of the 23 pairs of chromosomes in the sperm and egg; chance determines which member of the pair goes into the new sperm and egg
Crossing over: The process by which sections of DNA switch from one chromosome to another during meiosis, increasing genetic variability
What are Alleles?
- Different forms of genes; dominant (expressed if present), recessive (not expressed if dominant is present)
- Two of the same alleles (homozygous), two different (heterozygous)
How to Sex Chromosomes affect who we are?
- Two x chromosomes in 23rd pair (female), male have y and x
- Gene on the Y chromosome encodes a protein that triggers the formation of the testes
- Which produce testosterone, takes over the molding of maleness
What is the Disadvantage of being a male genetically?
- The Y chromosome has only about a third as many genes on it as the X chromosome
- Therefore males inherit more disabilities (colour blindness)
What are some Genetic Diseases and Disorders?
- Recessive gene: PKU, sickle-cell anemia, cystic fibrosis
- Single dominant gene: Huntington’s disease
- Sex-linked inheritance: Fragile-X syndrome, hemophilia
- Errors in meiosis (Down syndrome)
-
In some cases, as with sickle-cell anemia, what can a gene have?
Both
- Deleterious effects: A debilitating blood disorder when both alleles are present
Benefits: Protection against malaria, a blood parasite that can’t live and grow well in oval blood cells
Many syndromes are known to have a genetic basis. What are the specific genetic mechanisms have not been established yet?
- Dyslexia
- Tourette’s Syndrome
- Autism
- Cystic fibrosis
- ADHD
- Depression
- Schizophrenia
- Anxiety
What is Polygenic Inheritance?
- When traits are governed by more than one gene
What is the Case of PKU?
- Phenylketonuria: defective gene on chromosome 12 that is unable to metabolize phenylalanine
- Early diagnosis and properly restricted diet can help avoid mental problems
What do Regulatoratory Genes do?
- Largely control the switching “on and off” of genes
- Only when these are turned on can Genes influences development and behaviour
- A major force in both evolution and development
- This is because there appears to be a general toolkit for building bodies. They are the final product.
What is Epigenetics?
- How genes and the environment work together to produce/develop an organism
- Future of developmental studies, eductionist approach, extremely challenging in humans
How has the Evolution and brain development differed from other species?
Humans have a much larger brain than is expected for body size, more cortical neurons
What is the timeframe of a normal development
- Brain Development is between Birth and 21 years old.
- Migration has created a differentiation within people and how long this is for each person
What is Synaptogenesis?
- Cell death and pruning
- Synaptic rearrangement
What is Neurogenesis?
- Growth of neurons through cell division
- Nerves
What is brain plasticity?
- The ability of the brain to change
How do experiences affect synaptogenesis?
- Synapses are formed and maintained by experiences
- Synapses are formed as a result of unique experiences of the individual
What happens when you get a brain injury during development?
- Kennard effect: younger brains tend to “heal” better
