Module 3 Flashcards
What is a selection pressure
Factors that exist in an environment that make it easier for some organisms to survive
What are the two types of selection pressures
Abiotic and biotic factors
Give example of abiotic factors
Availability of food, climate, water
Give examples of biotic selection pressures
Predators, competition of mate, food , disease
State a type of selection pressure
Directional selection
Define directional selection
Natural selection that favours one extreme of the population for that trait
Abundance refers to
The numbers of a population
Distribution refers to
The spread of a population
Formula for abundance
Number of individuals/ size of area
What is the carrying capacity
The maximum equilibrium number of individuals of a species that can be supported indefinitely in a given population
What causes a carrying capacity
Resources becoming limited
Define symbiosis
Relationship between 2 species living in close proximity in which at least 1 of them benefits
State the three types of symbiosis
Mutualism, Parasitism and Communalism
Explain mutualism
Both species benefit from the interaction
Example of mutualistic relationship
Honey eater and grevilla (flower)
Explain parasitism
One species (parasite) benefits from the interaction while the host is harmed but not killed
Example of parasitism
Tick and dog
Explain commensalism
One species benefits from the interaction while the other neither benefits or is harmed
Example of commensalism
Cattle and egret
Define intra specific competition
Between same species
Interspecific competition is and an example is
Between different species
Cheetah and lion 🦁
Define disease
A condition that adversely affects the normal functioning of an organism
What factors influence the distribution and abundance of populations in ecosystems
Predation, competition, climate
Calculate estimated abundance formula for plants
(Total number of plants/(area of each quadrant * number of quadrants)) X total area
Measuring the estimated population using capture recapture method
(1st capture * 2nd capture )/ (no marked in 2nd capture)
Cane toads were brought in 1935 as a control for
Greybqck cane bettle in sugar plantations
Name some adaptations made by cane toads
Ability to disperse faster Feed at night _nocturnal Absorb water through skin Lower immune system Prone to arthritis
Adaptations to the red belly snake due to cane toads
Smaller jaw to be unable to consume the cane toads due to toxin
Adaptations made by the northern quoll
Developed a toad aversion mechanism
Define spatial sorting
A process that results in the accumulation of genes that are good for dispersal without there having to be an advantage to reproduction or survival
What control was introduced to stop the spread of prickly pear which was introduced to start cochineal dye industry
Cactoblastis cactorum …moth
State the 3 main types of adaptations
Structural, physiological and behavioural
Give one example of a structural adapts for a plant and animal
🌲 calandrinia- is a succulent meaning it has fleshy stems or leaves that swell up to retain moisture.. increases survival during dry periods
🦁Red Belly Snake -change head size to avoid eating cane toads
Give a physiological adaptation of fauna & flora
🌲 Deciduous beech loses leaves (abscission) in winter and undergoes dormancy (survive in low temp, availability of water and light)
🐁Spinifex hopping excrete the most concentrated urine to reduce amount of water to survive in harsh desert climate
Give a behavioural adaptation example for flora and fauna
🌲 Venus flytrap
-closes the trap to catch an insect
🦘 Red kangaroo
-seek shade in the heat of the day
Bilby -hide in burrows
Wallabies - lick wrist where there are dense blood vessels to cool then down 🩸
Give an example of a social behaviour
When meerkats search for food underground
One stand watch and makes distinctive calls when there’s a predator
Stand on hind legs and search for predator
Natural Selection is
A process in which creatures with more favourable traits have a higher likelihood of survival and reproduce to pass on trait to offspring
State the 4 principles of Darwin’s Theory
Variation < selection pressure introduced to environment< individuals with favourable trait live< reproduce and pass on the traits
Name Darwin’s observation and how it relates to his theory of evolution by natural selection :Finches on Galapagos Island
Charles collected 14 different species
Eg Warbler finch - Insect eater
Cactus ground finch - cactus eater
Different beak shape
Name Darwin’s observation and it relates to his theory of evolution by natural selection Australian Flora
Eucalyptus link between harsh environments and the adaptations observed in the vegetation
Trees in Aus and other southern continents are evergreen as opposed to those in northern hemisphere
Name Darwin’s observation and it relates to his theory of evolution by natural selection Australian Fauna
Platypus = Water rat in
Rabbit = rat kangaroo in Eng
Magpies = jackdaws in Eng
✨let him to the idea of convergent theory
Ant lions same genus but different species in Eng —idea of divergent theory
What is the other name for divergent evolution
Adaptive radiation
Explain biological diversity in terms of the theory of evolution by examining the changes in and diversification of life since it first appeared in the earth
Abiotic 👉 biotic (primordial cells as a result of abiogenesis) Prokaryotic 👉 Endosymbiosis Eukaryotic 👉Sexual reproduction Pro use binary fission Eu use meiosis and fertilisation (more variety) Multi cellular organisms 👉 Animals Vertebrates 👉 Evolution to land Dinosaurs 👉 Modern descendants
State 3types of biodiversity
Genetic, Species and Ecosystem
Give 4 ways how a species may diverge to give rise to two different species
- Parent population is divided by a geographic barrier
- There is no gene flow between daughter population
- Mutations may arise in in population
- Different selection pressures operate on each population
What is a species
Group of organisms that can produce fertile offsprings
Define micro evolution
Change that occurs in a small scale within a population due to mutations in genes resulting in new alleles , increase in frequency of a certain trait within a population
Define macro evolution
Changes that goes beyond the boundaries of individual species, origin of new species from an ancestor
The formation of a new species as a result of evolution is
Speciation
A collection of different genes of every individual present in a population is defined as
Gene pool
4 factors that may lead to micro evolution
Gene flow 🧬
Genetic drift
Mutations
Selection pressure
Genetic drift is
Random events that cause a change in allele frequency
Are the new individuals that have changed due to micro evolution the same species as their ancestors
Yes
Speciation is a result of micro evolution
No it’s macro evolution
State details describing the evolution of a horse
Started with Hyracoherium (omnivore teeth’s)
-it had 4 toes one each front and 3 back
-evolved to Epihippus
-more grinding teeth has diet changed to plant material
-Climate became drier … grasslands…selective pressure…speciation Miohippus genus
-longer legs (run from predators open area)
-Merychippus (better consume grass by developing hypsodont teeth and Jess developed ridges…grinding efficiency)
Lastly, Equus evolution of one toe, deep jaw,long neck and legs
What are hypsodont teeth
Teeth which grew continuously out of the gum as they were worn down by chewing grass
State the order of evolution of a horse
Hyracoherium < Epihippus
Evolution of platypus
Genetic evidence - suggest that monotremes split off first when mammals divided into 3 groups
Evolved from teinolophos< Cretaceous (Antarctic circle dark)
Platypus and echidna share common ancestor
Can locate their prey using electrical impulse given by muscle - convergent with sharks, fish
Flat surface bill has electro receptors -animals give off electric signals
Large surface area of bill.
Nocturnal
Define convergent evolution
Is the process by which organisms which are not closely related evolve to have similar traits because they have adapted to a similar environment
Give an example of convergent evolution
Sharks and dolphins (dorsal fins and streamlined bodies)
Define convergent evolution
Is the process by which organisms which have are not closely recent related evolve to have different traits because they have adapted to a similar environments
How does Darwin’s and Wallace’s Theory of Evolution by Natural Selection explain convergent evolution
A selection pressure is introduced into the environment and natural selection provides a mechanism which selects tte best suited traits to pressure
How does Darwin’s and Wallace’s Theory of Evolution by Natural Selection explain divergent evolution
Selection pressure is introduced to the species and the best traits are selected via natural selection the species evolve because of the different pressures faced
How is punctuated equilibrium different from gradualism
P suggests short rapid periods of change new species emerge due to new S.P followed by stasis population remains unchanged
G suggests species change slowly and uniformly over long periods of time
State the 5 evidences that support Darwin and Wallace’s Theory of Evolution by Natural Selection
Biochemical evidence Comparative embryology Comparative anatomy Biogeography Palaeontology (study of fossils)
Evidence drawn from biochemical evidence
Similar molecules or biochemical processes indicates common ancestor
Eg ATP, Nucleic acid
Cytochrome C respiration protein common btwn humans and rhesus monkey difference of 1 amino acid
Explain how DNA hybridisation happens
DNA is heated < combine single strands of DNA < Cool to allow renaturation < Determine degree of hybridisation
Give an example of comparative anatomy
Pentadactyl limb eg of homologous structure
Give an example of an transitional form
Archaeopteryx -intermediary organism as birds evolved from reptiles
Fossils can be dated in two ways which are
Absolute dating and Relative dating
Absolute dating can
Give the actual age
Relative dating can
Indicate whether a fossil is older or younger
Give 2 examples of Absolute dating methods
Fission tracking and Radiocarbon dating
Give two examples of relative dating methods
Chemical analysis, stratigraphy, bio stratigraphy
Give and explain an example that demonstrates modern evolutionary change
Antibiotic-resistant strain bacteria
Follows 4main principles of evolution
How has bacterial evolution been sped up by humans
Overuse
Treat wrong infections
A term used to describe the relative position of a species within an ecosystem
Niche
Which principle states that more than one species cannot occupy the same ecological niche …competition
Competitive exclusion principle
What are the consequences of predation
Relationship detrimental to prey
Forces adaptation of organisms
Predators become better at catching prey through natural selection
Enhanced traits such as claws , speed … food
Prey become better at avoiding predators
Traits such as camouflage or minimal movement
What are the consequences of competition
By the competition of principle, it may result in extinction of a competition species or adaptation to new resources
Drive for evolution, leads to divergent evolution and selects new mutations and the environment changes
If parasitism relationship causes death of an organism it is called
Necrotrophic
If parasitism relationship requires continued survival of an organism it is called
Biotrophic
Disease can be caused by
Parasites, a result of nutrient deficiency, due to chemicals and pollutants or result of climate (coral bleaching)
Name two methods of measuring a population (plants) & animals
Quadrant method
Capture recapture method
Formula for capture recapture method
(1st catch * 2nd catch)/(# marked in 2nd catch)
Explain a recent extinction event
Name: San Cristóbal vermilion flycatcher
Found: Galapagos
Cause: introduction of invasive rats on the island which fed on the birds eggs
Invasive plants replaced endemic vegetation leading to decline insects that consumed them thus lack of availability of food led to the birds death
Effects : loss of biodiversity
