Module 3: Biological Diversity IQ1 Flashcards
Define an ‘individual’
An individual is a single organism, such as one plant, fungus, animal or unicellular organism.
Define population
A group of organisms of the same species that interact with each other.
Define community
A group of species that occur in the same area and interact, or cold interact with each other.
Define biosphere
The region of Earth’s land, sea and atmosphere that is occupied by living things.
Define biome
A group of communities that have similar structure and habitats extending over a large area.
Define habitat
The environment (place) where an organism lives.
Define microhabitat, provide an example.
Smaller area within a habitat (e.g burrow or tree canopy**
Define ecosystem
A system formed by organisms with one another and their physical environment.
Ecosystems
What are the 5 major ecosystems?
- Aquatic
- Forest
- Grasslands
- Tundra
- Desert
can be further divided into specific categories, such as freshwater, marine, savanna, tropical rainforest, temperate rainforest, and taiga
Ecosystems
Can ‘ecosystems be found within ecosystems?’ Explain
Yes, like nesting dolls, ecosystems can exist within ecosystems.
E.g A forest biome, contains distinct microcosms (sub-ecosystems).
- The tree canopy harbors specialized species adapted to its light levels,
- while the forest floor fosters decomposers in its shade.
Even a tiny pond becomes its own ecosystem.
This nested structure highlights the intricate web of interactions that sustains the overall health of the biome.
ecosystems - Australian examples
Identify the variety of Australian ecosystems
- Desert or arid zonne
- Shrubland
- Open woodland
- Scierophyll forest
- Temperate rainforest
- Tropical rainforest
What are the conditions of the Open Woodland?
- Seasonal climate with distinct wet and dry seasons.
- Moderate to low rainfall, often concentrated in the wet season.
- Various soil types, typically moderately fertile and well-drained.
- Scattered trees withsparse canopies, allowing significant light penetration.
- High biodiversity of plants: oak, acacia, eucalyptus
- and animals: deer, kangaroos, songbirds, snakes & lizards
Australian examples of ecosystems
What are the conditions of the scierophyll forest?
- Mediterranean climate with hot, dry summers and mild, wet winters.
- Common tree species include eucalyptus, acacias, banksias, and casuarinas.
- Diverse animal species: parrots, kangaroos, koalas, snakes & lizards
- Adaptation with coping with fire
Australian examples of ecosystems
What are the conditions of the shrubland?
- Climate: Often semi-arid to Mediterranean, with hot, dry summers and mild, wet winters.
- Precipitation: low to moderate, with seasonal variations.
- Vegetation: Dominated by shrubs, often drought-resistant species adapted to arid coinditions.
- Soil: Often shallow and rocky, with low fertility and poor water retention.
- plants: succulents, wildflowers
- animals: small mammals like rabbits, ground squirrels, insects: butterflies, bees, grasshoppers
Australian examples of ecosystems
What are the conditions of the temperate rainforest?
- Climate: Cool to mild temperatures with high rainfall.
- Precipitation: Abundant, exceeding 2000 mm annually.
- Vegetation: Tall, evergreen trees with dense canopies.
- Understory: Diverse with smaller trees, shrubs, ferns, and mosses.
- Soil: Nutrient-rich and well-drained.
- Biodiversity: High levels, including mammals, birds, amphibians, and invertebrates.
Australian examples of ecosystems
What are the conditions of the tropical rainforest?
- Climate: Consistently warm temperatures, little seasonal variation.
- High Precipitation: Abundant rainfall, evenly distributed throughout the year.
- Humidity: High levels of humidity, typically exceeding 80%.
- Soil: Relatively poor in nutrients due to rapid decomposition and leaching.
- Canopy Structure: Dense overhead cover formed by tall trees’ overlapping branches and leaves.
- Plants: Kapok, Brazil nut, Mahogany, Orchids, Bromeliads, Coconut palm.
- Animals: Jaguars, Sloths, Toucans, Anacondas, Poison dart frogs, Butterflies.
exceptionlly diverse
Abiotic & Biotic factors
What are abiotic factors and biotic factors? Give examples for each.
Abiotic factors – non-living components of the environment
e.g physical - temperature, light and chemical – pH, water, gases, soil minerals.
Biotic factors – living components such as bacteria, fungi, plants and animals, food resources, predator/prey relationships.
What is an environment?
An environment/habitat/ecosystem is a place where organisms interact and are influenced by the biotic and abiotic factors.
Aquatic environments are some of the most complex and dynamic ecosystems on earth, they can be shaped by factors such as:
1. Lithospheric elements:shape of surrounding landscape,processes of erosion,transportation and despositions, as well as sedimens and suspended particles in the water
2. Energy: in the form of waves and tidal movements
3. Water chemistry: fluctiations in oxygen levels and freshwater vs saltwater environments
4. Water physics: factors of specific gravity, heat capacity, turbiity, light penetration and upwelling
Selective Pressures
What are selective pressures?
Selection pressures are external agents which affect an organism’s ability to survive in a given environment
- Selection pressures can be negative (decreases the occurrence of a trait) or positive (increases the proportion of a trait)
- Selection pressures may not remain constant, leading to changes in what constitutes a beneficial adaptation
What are examples of Selection pressures?
(remember PANDA PAW)
Density dependent factors
Predators
Availability of resources
Nutrient supply
Disease
Accumulation of wastes
Density independent factors
Phenomena (e.g natural disasters)
Abiotic factors
Weather conditions
Abiotic pressures
What is light and how does light affect the ecosystems?
The amount of solar energy an environment receives, changes with latitude, season and time of day.
* Plants use solar energy for photosynthesis
* Light also affects many plant and animals behaviours
- Affect plant root growth
- Promote leaf expansion
- Affect a species growth, colour, metabolism, circadian rhythms, migrations and production patterns
How does temperature affect the ecosystem?
- Leads to dormancy, a state in which an organism’s growth,development and activity temporarily slows, or stops, to conserve energy.
- It occurs when temperatures are not favourable. Most animals who hibernate reduce their body temp.
E.g
-The Artic squirrel, reduces it’s body temp to sub zero.
-Australian banksia species, require at least 2 min in 500 degrees to melt the resin on its pods and release its seeds for germination to occur. - Can affect species distribution
Abiotic effects
What is weather? How does weather affect the ecosystem? Provide an example.
Short-term variation in atmospheric conditions, such as temperature, solar radiation, wind, moisture and atmospheric pressure, change the:
- physical environment
- affect the growth
- behaviour
- and reproduction of some organisms.
Example: A garden, in which plant leaves wilt after several days of low rainfall and high temperatures. In the animal kingdom, researchers have discovered that birds can predict changes in weather using their “internal barometer”, which senses subtle changes in air pressure, which then affects the birds behaviour such as flight patterns and feeding.]
Abiotic factor effect on ecosystem
How does water affect the ecosystem?
Found through the Earths’ hydrosphere, not all water is readily accessible for an organisms need. The availability of water in an organism’s physical environment will depend on factors such as rainfall, the presence of fresh or saltwater, where the water is “locked” in glaciers, and the amount of water vapour found in the air(humidity).
Plants and animals have a wide range of structural, physiological and behavioural adaptations to overcome changes in water availability in their environment.
Abiotic factor - water -> aquatic environments
What is an example of a complex aquatic environment?
Estuaries
- Where marine saltwater is diluted by freshwater where the river meets the sea, this environment contains high salt levels and waterlogged land.
- Highly specialised organisms, such as mangroves have evolved adaptations to tolerate the fluctuating conditions of estauries.
How does shelter affect ecosystems?
Shelter is both beneficial for plants and animals as it is protection from weather and predators
- provides space for growth, development and social activity. - Shelter can be formed by biotic elements in the environment, such as a tree providing shade for a lion, or can be abiotic, such as a wombat sheltering in a burrow
What is topography?
Topography is the shape of a land which affects water runoff and soil type and can create microclimates within an environment.
What are examples of topography?
- Aspect: the directon a slope faces
- causes variation in the amount of sunlight received by an area of land
- in the southern hemisphere, slopes with a southerly aspect generally have colder oditions and often receive harsher winds. - Altitude: height of a land mass above sea level
- as altitude increases, air pressure and temperature decrease, as well as amount of readily available oxygen.
What are human impacts on the biotic environment?
-Trawling certain fish species can reduce their abundance and decrease food availability for higher predators.
- Artificial selection – selectively breeding organisms with specific traits. E.g hens that lay larger eggs.
Trawling - catch with a trawl net, sift through as part of a search
Why do human activities have such far-reaching consequences for so many species?
Explain using an example.
Human activities have far-reaching consequences for many species due to several interconnected factors:
- Habitat alteration: Conversion of natural habitats into human-dominated landscapes reduces available habitat and isolates populations, as seen in forest conversion for agriculture.
- Introduction of non-native species: Non-native species can become invasive and outcompete natives, as seen with the cane toad’s impact on Australian predators.e.g European Rabbit: Introduced to Australia, the European rabbit has become a major agricultural pest and threatens native plant species through overgrazing.
- Pollution: Pollution harms organisms, disrupts ecosystems, and alters species interactions; agricultural runoff contaminates water bodies, impacting aquatic ecosystems.
- Climate change: Human-induced climate change alters temperature patterns and precipitation regimes, affecting species distribution and phenology, as seen in disruptions to plant-pollinator relationships.
Organism tolerance
What happens when an organism is outside its ideal range for a particular factor?
The organism will experience stress. In extreme cases it may die.
Keystone species
What are keystone species?
Species that play critical roles in the structure and functioning of an ecosystem.
Keystone species
What are some examples of keystone species?
KS: species that play critical roles in the
structure&functioning of an ecosystem
- Great White Shark,
on top of the food chain, keeping the seals fish and sea lions numbers stable. - Northern quoll (native cat),
this species has become endangered due to bushfires andfeeding on poisonous cane toads. This animal feeds on a range of foods including birds, mammals, reptiles. Through feeding/hunting, the quoll helps control the numbers of its prey species. - African elephants, eating small trees.
Without the elephants the savannas would beinvaded by shrubs and eventually become forest.
Keystone species
What happens when a keystone species is removed?
The ecosystem becomes less stable.
What is the meaning of tolerance range?
a range of conditions in which a organism can survive.
Relationships - Symbiosis
What is symbiosis?
The living together in close association of two different kinds of organisms.
Relationships - Symbiosis
What are the 3 different symbiosis relationships?
- Mutualism - beneficial to both organisms involved
- Parasitism - where one organism, the parasite, lives on or in another organism, the host, causing it some harm.
- Commensalism - when one organism benefits and the other derives neither benefit nor harm.
Relationships - Symbiosis
What is mutualism? Give an example.
symbiotic relationship between two organisms of different species in which both individuals benefit from the association.
Example: Bee and flower
- Mutualistic Interaction: Bees visit flowers to collect nectar, which they use as a food source. In the process of feeding, bees inadvertently transfer pollen from one flower to another, facilitating the pollination process.
- Benefits: The bees benefit by obtaining nectar as a food source, while the flowers benefit from the pollination services provided by the bees, leading to successful reproduction and seed production
Relationships - Symbiosis
What is commensalism? Give an example.
symbiotic relationship between two organisms of different species in which one organism benefits, and the other is neither harmed nor benefited.
Example: Remoras (fish) and sharks (fish).
- Commensal Interaction: Remoras attach themselves to the bodies of sharks using a suction cup-like structure on their heads. They travel alongside the shark, feeding on scraps of food left behind by the shark’s meals or on parasites attached to the shark’s skin. The presence of the remoras does not significantly affect the shark.
- Benefits: Remoras benefit by gaining access to food sources and protection from predators while being transported by the shark. The sharks are not directly affected by the remoras’ presence but neither benefit nor suffer harm from it.
Relationships - Symbiosis
What is parasitism? Provide an example.
symbiotic relationship between two organisms of different species, where one organism, the parasite, benefits at the expense of the other organism, the host.
Example: Tick (parasite) and dog (host).
Parasitic Interaction: Ticks attach themselves to the skin of dogs and feed on their blood. While feeding, ticks can transmit diseases such as Lyme disease or Rocky Mountain spotted fever to the dog. The presence of ticks can cause discomfort, irritation, and potential health issues for the dog.
Benefits: The tick benefits by obtaining nourishment (blood) from the dog and utilizing it for reproduction and survival. However, this comes at the expense of the dog, which may suffer from the negative effects of tick infestation, including disease transmission and skin irritation.
Relationships - Alleopathy
What is an alleopathic relationship?
a biological phenomenon where one plant species releases chemicals into the environment that affect the growth, development, or germination of other nearby plants.
Population changes due to selection pressures overtime
Factors that influence population change
- Rate of birth
- Immigration (coming into a population)
- Emigration (leaving)
- Changes in physical environment (spread of weeds and animal pests)
- Behaviour of the organism
Population changes due to selection pressures overtime
What are non-native species?
- not naturally found species which are added to an area.
- Can be natural - migration due to habitat loss
Population changes due to selection pressures overtime
What are native species?
- Native species are found in an area as a result of nature processes only.
- They have developed naturally in a given area over time.
Population changes due to selection pressures overtime
What are invasive species?
An invasive species is an introduced, non-native organism (disease, parasite, plant, or animal) that begins to spread or expand its range from the site of its original introduction and that has the potential to cause harm to the environment, the economy, or to human health
Population changes due to selection pressures overtime
What are the four major threats invasive species pose?
1. alter the ecosystem
2. destroy forests, crops or both
3. reduce the beauty or use of the land
4. introduce diseases or other negative health affects
What is the abundance of a species?
Describes how many of them there are.
Abundance
How does the abundance of organisms change over time?
Increase due to births and immigration
Decrease due to deaths and emigration
Immigration:act of coming to your own country
Emigration:act of leaving
What is the distribution of a species?
Where the organisms are found.
What is an example of distribution?
Platypus
- they usually make their homes in freshwater areas
- waddle onto the river banks to dig burrows with ther claws.
- have been found in plateaus, lowlands, topical rainforests and the cold moutains of tasmania and the Australian Alps.
What is an adaptation?
an inherited characteristic that increases the likelihood of survival and reproduction of an individual organism in a particular environment,
What are the three main types of adaptations?
- Structural
- Physiological
- Behavioural
Adaptations
What are structural adaptations? Provide an example.
Anatomical or morphological features that improve an organism’s ability to cope with abiotic and biotic factors in their environment, increasing their chances of survival and reproduction.
E.g thick fur and blubber in seals to help with the cold/insulation
What are physiological adaptations?
Physiological adaptations are an internal body process to regulate and maintain homeostasis for an organism to survive in the environment in which it exists.
E.g. sweating in mammals to cool down slowing down metabolism when hot
What are behavioural adaptations?
actions that an organism takes to improve survival or reproduction, particularly with changes in their environment
*E.g. migration, birds will move in the winter to warmer places for food *
