Midterm 2 Flashcards
(131 cards)
1
Q
Therapsida evolution included which characteristics?
A
Increases metabolic rates
Skeletal modifications (muscular diaphragm for enhanced breathing)
Soft tissue secondary palate (allowed breathing while eating)
2
Q
Lineage within therapsids (evolved as Mammalia)
A
Cheek teeth with multiple cusps
Mobile muzzle with lips and whiskers
Scroll like bones in nasal passages to warm and moisten air as it’s breathed in
Helped find and grasp food, conserve body heat
3
Q
Mammalia evolution
A
Small bodies (shrew-sized)
Generally carnivores
Females nursed with milk
Hair or fur (for insulation)
4
Q
3 major lineages of mammals arose
A
Monotremata (egg laying)
Masupiala (pouch)
Placentalia (placental)
5
Q
Major adaptive radiation after Cretaceous-Paleogene extinction
Which characteristics?
A
Primates: Large brains Complex behaviour Forward facing eyes (binocular vision) allowed for depth perception (useful for moving between branches) Flat cheek teeth, large canines Mobile shoulder joints Opposable thumbs and toes Nails Tactile pads Mammary glands Birth smaller litter
6
Q
- Mobile elbow and ankle joints, long grasping fingers
- Low crowned cheek teeth
- Non-forward facing vision
A
- clinging and climbing slender branches
- Feeding on flowers and insects
- Poor vision so not visual predators
7
Q
Unspecialized dentition
A
Feed primarily on fruit
8
Q
Low sagittal crest
A
Large chewing force
9
Q
Long tail, strong feet, opposable thumbs
A
Moving well through branches
10
Q
Prehensile (grasping) tail
A
Help swing from trees
11
Q
Thickly enamelled cheek teeth
A
Hard fibrous diet
12
Q
Foremen magnum central
A
Bipedal motion
13
Q
Foramen magnum at back of skull
A
Fully quadruple
14
Q
Foramen magnum at slight angle
A
Knuckle walking ape
15
Q
Long arms and opposable big toe
A
Spent time in trees
16
Q
Massive jaws
Large cheek teeth
Sagittal crest along top of braincase for attachment of large jaw muscles
A
Tough plant material diet
17
Q
Reduced cheek teeth
A
Cooking food
18
Q
Big variation in size
A
Suggesting they were sexually dimorphic
Males and females differing in size
19
Q
Reduced sexual dimorphism
A
Primarily monogamous
20
Q
Out-of-Africa hypothesis
A
Homo sapiens originated and evolved into modern form in Africa
Them migrated and interacted with other Hominina species throughout Europe and Asia
21
Q
Molecular evidence for out-of-Africa hypothesis
A
Genetic diversity greatest in Africa
22
Q
Bipedalism hypotheses
A
Less exposed surface area for sun damage
Hands free for foraging and carrying tools
Efficient migration
23
Q
Pelvis modifications
A
Chimps: long and flat
Humans: bowl shaped for balance in upright primates
24
Q
Femur modifications
A
Chimps: straight
Humans: angled slightly inward allowing us to kick forward for bipedal stride
25
Feet modifications
Chimps: opposable great toe
Humans: heel large, foot arched, toes allowing leverage
26
Brain size
Increases brain size
Can manufacture complex tools
Foraging and hunting more complex
Complex social lives
27
Tools
| Orangutans
Poles to trap fish and twigs to obtain honey and termites
28
Tools
| Gorillas
Sticks to probe water depth and poles for balance while walking in water
29
Tools
| chimpanzees
Strip leaves from twigs to extract termites, collect ants and honey
Use sharpened sticks to extract small prey
Spongelike mats to collect water
30
Tools
| Bonobos
Grooming with small sticks
| Large leaves for rain cover
31
Tools
| Oldowan
Flakes: butchering tools or used to sharpen sticks
Cores: pounding, chopping, scraping hides
Extractive foraging for roots and butchering large prey
32
Tools
| Acheulian
Hand axes for butchering prey
| Skinning, severing joints, shearing meat from bone
33
Tools
| Mousterian
Hunting large game
| Full-scale hunting
34
Weapons and refined tools
Knives, chisels, drills, harpoons, spears, bows and arrows
| Cooperating and sharing behaviour
35
Weapons and refined tools
| Materials
Bone, shell, antler, wood, ivory
| For artwork
36
Controlling fire and cooking
| Benefits?
Cooking softens fibres and reduces chewing time, increases food metabolized
Killed potential pathogens
Increased number of calories to supply needs of brain
Protect against predators at night
37
Reduced jaw musculature in Homo
Humans have a mutant gene that led to 80% reduction in jaw musculature
MYH16 gene
38
Brain ossification
Primate brain case formed by cranial bones joined by fibrous elastic sutures that ossify (become bony) during development
allows braincase to stretch and deform
Human brain cases grow into early adulthood (delayed ossification)
Brain case must be ossified in apes that develop large jaw muscles, or brain case could be pulled to pieces
39
Brain size
Brains are metabolically expensive
| Gorillas don’t have enough time to eat enough food to support a large brain
40
Reduced jaw
| Maladaptive
Cooking made producing large musculature unnecessary
41
Pelvic girdle size restrained
Bipedal hominina constrained to deliver babies with small brains
Brain growth can continue after birth
42
Clothing
Premature stop codon in gene responsible for fur in humans
Analyzed lice species to estimate when humans lost fur and began wearing clothes
Head and body lice inferred to share a common ancestor when humans started wearing clothes
43
Melanin evolution
| UV
Melanin functions as sunscreen
UV radiation can cause skin cancer (melanin protects)
Chimpanzees and early Hominina are fair
44
Melanin evolution
| Folate
Essential vitamin
Deficiencies lead to birth defects
UV radiation causes folate breakdown
Natural selection operates on skin cancer and folic acid requirements favouring individuals with dark skin in regions with high UV
45
Melanin evolution
| Vitamin d
Necessary for growth and immune system
Dark skin requires more exposure to sun to obtain vitamin d
Fairer skin favoured in regions with less UV
46
Malaria resistance
HbA is most common type
HbS caused by mutation
Homozygous get a deadly disease
Heterozygous get resistance to malaria
Frequency of HbS highest in regions where malaria is common
47
Lactase evolution
75% of humans cannot properly digest milk after 2 years old
Many mutations in regularly gene that controls lactase
Geographic distribution of pastoralist and lactase persistence overlap closely
48
Menopause evolution
Grandmother hypothesis: menopause evolved due to inclusive fitness benefits gained by older women assisting in rearing grandchildren rather than giving birth and caring for own children
Mothering hypothesis: mother contributes to reproductive success of her children directly by providing extended care
Lifespan artifact hypothesis: evolved due to increased human longevity
Mate-choice hypothesis: evolved due to change in mating behaviour involving only adults
49
Misconceptions about human evolution
Humans evolved from chimps
The human mind is too complex to have evolved
Humans stopped evolving
50
Ecology
Study of factors that determine the distribution and abundance of organisms
Flows of energy in biological systems
51
Organismal ecology (behavioural/physiological)
How an individual organism interacts with its environment
52
Population ecology
How and why does a population change over time
Interactions between individuals (infraspecific)
Interactions with conspecific individuals (same species)
53
Conspecific
Members of same species
54
Infraspecific
Interactions within species
55
Heterospecific
Member of different species
56
Interspecific
Interactions between species
57
Community ecology
Nature of interactions between species and their consequences
Interspecific interactions
58
Ecosystem ecology
How chemical elements that act as nutrients cycle through an ecosystem
59
Global ecology
Studies effects of human impacts on the biosphere
60
Abiotic limiting factors
```
Light
Nutrients
Temperature
Water
Salinity
Disturbances (ex. Wildfires)
```
61
Liebig’s law of the minimum
Organismal distributions are determined by the most limiting factor
If u change something in a system (ex. Change temp) and the system responds (changes), it is the limiting factor
62
Niche
Range of environments that allow persistence (growth and reproduction) of a species
63
Top-down factors
Regulate rate of loss rather than rate of production
Biotic: ex predators
Abiotic: ex fire
64
Dispersal
Movement of an individual from birth place to location where it lives and breeds
65
Biome
Region with distinct abiotic factors and vegetation
66
Net primary product
Total amount of biomass generated by fixation of carbon per year minus amount oxidized by cellular respiration
67
Aboveground biomass
Total mass of living plants exuding roots
68
Arctic tundra
Throughout arctic regions of northern hemisphere
Low productivity, low diversity, low aboveground biomass
Soil can be permanently frozen
Ground covered by low plants (no trees)
Low precip
Cold
69
Boreal forest
Low productivity
Low diversity due to low temp and low precip
Dominated by conifers
High aboveground biomass
70
Temperate coniferous forest
Primarily in coastal areas with mild winter and heavy precipitation
Coniferous trees
71
Temperate forest
Productivity and diversity are moderate
Dominated by deciduous trees
Moderate precip
72
Temperate grassland
Prairie
Generally low productivity but soils highly fertile
Grass dominated because conditions are too dry for tree growth
73
Subtropical desert
Extreme temperatures
Low moisture
Low productivity
Leafless plants (cacti)
74
Tropical wet forest
```
(Rain forest)
Favourable year round growing conditions
High aboveground biomass
High diversity
High productivity
Diverse evergreen trees
```
75
Water depth gradient
Light availability decrease with depth
Dark, cold, low productivity, nutrient accumulation
Light, warm, high productivity, nutrient depletion
76
Upwelling
Nutrients brought up to surface
77
Donor controlled
Whale falls, organisms live on dead whales
78
Chemoautotrophic
Cold seeps, hydrocarbons seeping out of ocean floor, just chemical energy to convert to energy rich compound
79
Benthic zone
Bottom of ocean
80
Photic zone
Receive sun to support photosynthesis
81
Aphotic regions
Don’t receive sunlight
82
Behaviour
Response to a stimulus
83
Phenotypic plasticity
Phenotype changing in response to environment
84
Proximate causation
Explains how actions occur
85
Ultimate causation
Explains why actions occur
| Usually based on evolutionary consequences
86
Optimal foraging
Hypothesis that animals maximize their feeding efficiency
| Longer travel distance = extra costs, more benefits (larger prey, ...)
87
Rate maximization
Maximize energy gain per unit time
| Energy gained / time spent
88
Rate maximization predictions
Be choosy when preferred prey are abundant
| When preferred prey are rare, eat whatever you can find
89
Searchers
S
| Hard time finding food, easy time handling it (s>h)
90
Handlers
h
Lots of food available
Takes a long time to digest/kill/chas
(h>s)
91
Fixed action patterns
Highly inflexible, inherited
| Ex. Yawns and sneezes
92
Learning
Change in behaviour that results from a specific experience in an individuals life
93
Innate behaviour
Require no learning, inherited
| Ex. Fixed action patterns
94
Why should receivers believe a signal
Frequency dependence: dishonest is rare, cost of believing is low
Dishonesty is difficult or expensive
95
Benefits of sexual selection
Males provide females with
| Good territories, defence, resource, good genes for offspring
96
Handicap principle
Only good males can afford good ornaments
| May do signalling because it’s expensive (push ups prove the lizard has lots of energy)
97
Altruism
Acting as to lower one’s fitness and enhance someone else’s
98
Self interest
```
Apparent altruism (helps both you and the group)
Working together (ex. Lions)
Helps of individual costs are low
```
99
Kin selection
Natural selection that acts through benefits to relatives
100
Hamilton’s rule
If benefits of altruistic behaviours are high, and of benefits are dispersed to close relatives, and of costs are low, alleles associated with altruism will be favoured by natural selection
Costs are worthwhile if costs to individual is less than value of benefits to kin
C < rB
r is relatedness
B is benefits
101
Eusociality
Workers sacrifice their own direct fitness to help rear queens offspring
102
Reciprocal altruism
Exchange of fitness benefits separated in time
103
Environment of Evolutionary adaptedness EEA
Humans used to be hunter gatherers for so long
Lived in small related interacting groups
Cooperation make evolutionary sense
Closer cooperation with kin
104
Population
Group of conspecifics living in same area at the same time
105
Enumeration
Typically for stationary organisms
| Count every organism in a plot
106
Mark recapture
Catch and mark organisms
Let them free
Recapture and count how many are marked
107
Distance sampling
Stand in one place and count as many individuals as you can see/hear
108
Species distribution models
Abiotic and biotic factors
| Usually most abiotic and land cover types
109
First law of ecology
Change in population size = birth - death + immigration - emigration
110
Senescence
Decreasing fecundity/increasing mortality at old age
111
Survivorship
Proportion of offspring that survive to a particular age
112
Negative density dependence
Acts against whatever is happening in the population
Ex. Crowding leads to less population growth which leads to less crowding
Keeps population in check
113
Type III
High juvenile mortality
But if they survive, have a high probability of survival
Steeper than exponential, then flattens out
114
Type II
Constant per capita survival, constant per capita mortality rate
Straight line on log scale
Exponential decline on linear
115
Type I
Senescence
Almost no one dies for a while, then crashes down at old age
On a linear scale concave down
On a log scale downward curving function
116
Linear scale
Shows absolute change
How many die
Straight line means constant number die per year
117
Log scale
Shows proportion change (fraction dying)
| Straight line means constant fraction dying per year
118
Fecundity
Number of female offspring per female
119
Iteroparity
Reproduce many times
120
Semelparity
Reproduce once
121
Precocial
Mature quickly
122
Altricial
Mature slowly
123
r selected
High fecundity
| Short life span
124
K selected
Low fecundity, long life span
125
Exponential growth
Density independent
Occurs when r doesn’t change over time
Population size doesn’t limit growth rate
Common in colonization of a new habitat
Constant per capita growth and death rates
126
Per capita rate of increase
r
| Difference between birth and death per individual
127
Logistic growth
Density dependent
| Linear decline in per capita growth rate
128
Density independent factors
usually abiotic
| Varying weather, catastrophe
129
Density dependent factors
Change in intensity as a function of population size
Usually biotic
Competition, disease, predation
130
Predator prey cycles
Predators kills prey (decrease growth rate)
Prey nourish predators (increase growth rate)
Induce population cycles
131
R
R > 1 means an increase in population
R < 1 means a decrease
Always > 0
