BIOL1030 U2

Taxonomy

The scientific discipline concerned with classifying and naming diverse forms of life

Phenotype

The observable physical traits of an organism in morphology

Genotype

The genetic makeup of an organism

Ecology

Where and how an organism interacts with other organisms and its environment

Life History Traits

Traits that affect how an organism survives and reproduces

The most common characteristics biologists use to define a species includes…

phenotypes, genotypes, ecology, and life history traits

Viable Offspring

Offspring that survive to adulthood

Fertile Offspring

Offspring that are able to successfully reproduce

Biological Species Concept

Members of a population that actually or potentially interbreed in nature and produce viable and fertile offspring

Reproductive Isolation

One species is unable to interbreed in nature to produce viable, fertile offspring with another species

Speciation

The process of a new species appearing

Morphological Species Concept

Characteristics such as body shape and structural features are used to group organisms

Advantages and disadvantages of the morphological species concept

It can be applied to asexually reproducing organisms and can be used on fossils, but it has subjective criteria and cannot account for convergent evolution and phenotypic plasticity

Pre-fertilization barriers to interbreeding

• Geological isolation

• Temporal isolation

• Behavioural isolation

• Mechanical isolation

• Gametic isolation

Geological Isolation

Geological barriers (mountains, oceans, rivers, etc) prevent interbreeding

Temporal Isolation

Different behaviours prevent interbreeding

Behavioural Isolation

Different behaviours prevent interbreeding

Mechanical Isolation

Physical/mechanically impossible physical traits prevent interbreeding

Gametic Isolation

An egg cannot be fertilised because of incompatible proteins in the egg and sperm

Post-fertilization barriers to interbreeding

• Zygote mortality

• Early mortality

• Hybrid sterility

Zygote Mortality

The fertilised egg dies

Early Mortality

The offspring dies before reaching reproductive maturity

Hybrid Sterility

The offspring of two species is unable to reproduce

Phylogenetics

The study of genetic information (DNA and RNA) and the similarities and differences of this information between groups of organisms

Branches

The lines of phylogenetic diagrams that represent the evolutionary ‘distance’ between taxa - often based on DNA data

Node

Each node on a phylogenetic tree is a divergence event and the node represents the most recent common ancestor

Operational Taxonomic Unit (OTU)

A group of organisms under investigation (the group at the end of a branch)

Monophyletic Group

Organisms descended from a single ancestor

Polyphyletic Group

Unrelated organisms descended from one or more ancestors - often used with shared characteristics

Paraphyletic Group

Includes a common ancestor but not all of its descendants

Information that can affect phylogenies

Technology advancement, the discovery or reclassification of new species, or the discovery of a new fossilised common ancestor

High Distinctness

Organisms that are genetically distinct from other organisms and can be distinct in the way they look, live, and behave - can help inform conservation priorities

Biogeography

The study of how organisms have come to occupy their places on the globe

Lattitudinal Diversity Gradient (LDG)

The tendency for species richness to increase when moving from the poles towards the equator

The Evolutionary Time Hypothesis for the LDG…

Suggests species richness relates for the length of time available for species to fill habitats and niches

The Area Hypothesis for the LDG…

Suggests that the more area, the more species, and the less the environmental change

The Species Energy Hypothesis for the LDG…

Suggests that species richness is higher where more environmental energy is available - more solar energy and water means more biomass

Ecological Time

Species richness is a consequence of ecosystem stability

Ecological Succession

The process of how ecosystems change over time and/or following disturbance

Biomes

Any of the world’s major ecosystem types, usually classified based on the dominant type of vegetation

Species richness

The number of species in a biological community

Species Abundance

How rare/common a species is compared to other species in a defined location or community

Species Diversity

The number and relative abundance of a species in a biological community

Biomass

The total quantity or weight of organisms in a given area

Viable Population

A self-supporting population with sufficient numbers and genetic variety among healthy individuals that have distributed well enough to ensure a high probability of survival

Primary Production

The amount of light energy converted into chemical energy by autotrophs in an ecosystem

Colonise

The process in which a species spreads to a new area and becomes integrated into the community

Ecosystem Stability

An ecosystem is said to possess ecological stability if it is capable of returning to equilibrium after perturbation or if it does not experience unexpected large changes in its characteristics over time

Ecological Disturbance

A temporary change in environmental conditions that causes a pronounced change in an ecosystem, a disturbance that can be natural or the result of human impacts

Economic Value

The financial importance of a species as a commodity

Utilitarian Value

How useful something is to humans such as medicinal use or how it can contribute to the freshness of the water or the cleanliness of the air

Instrumental Value

High genetic diversity or evolutionary distinctness

Environmental degradation has been correlated with…

Increased disease transfer from animals to human, an increase in physical diseases like cancer, and reductions in physiological health

The choice to conserve (or not to conserve) is ultimately…

Subjective and based on our perceived importance of species or the ecosystem in question as well as the tools and resources available to conserve

How do scientists identify priority species?

They look at its function in an ecosystem, whether or not they are Evolutionarily Distinct and Globally Endangered (EDGE), and if it is in a biodiversity hotspot

Keystone Species

A species that helps define an entire ecosystem, but is not always the largest or most abundant

Umbrella Species

A species that is valuable due to their large habitat range, and protection of these species protects many other species with smaller habitat requirements

Flagship Species

Acts as symbols or mascots for habitat protection - often large mammals, the “flagship” title relies heavily on social, cultural, and/or economic appeal

EDGE Framework

Methodically ranks species based on how evolutionarily distinct and how endangered they are

Pros of EDGE Framework

Species that aren’t necessarily charismatic or of economic important receive conservation efforts

Endemic Species

A species that is found in a certain area and nowhere else on earth

Biodiversity Offsets

A tool used to prevent the ‘net loss’ of biodiversity caused by development - generally considered as the final option in the mitigation hierarchy

Sustainable use policies can be divided into 2 categories -

Harvest and trade, to regulate how much is harvested and what/how much is traded and where it came from

How do we conserve species and ecosystems?

• Habitat protection - protected area establishment, resource protection

• Habitat management - biodiversity offsets, invasive species control

• Species management - sustainable use, breeding and reintroduction

What is Country?

Country is considered home - the landscape, skyscape, and waterscape - plants, water, animals, rocks, etc. - embraces seasons, stories, lore, art, song, dance, and creation spirits and laws of the land

Country is both…

A place of belonging and a way of knowing

First peoples mainly connect with their Country through…

Geographic locations and being on the land

The Western perspective on ‘nature’ is that…

People and nature are separate and there is a hierarchy to nature with humans alone at the top

First Nations perspective on ‘nature’ is that…

People and nature are intertwined in a complex network and are inseparable from that network - incorporates people, places, plants, animals, and ancestors into the network

Indigenous peoples focus more on ___________ than _________ in world views.

Relationships, objects

Kinship Systems…

Allocate particular roles, responsibilities, and obligations to specific kin

Kin can be…

People, animals, plants, places, and totems

People an dingoes are considered one being because…

They share the same experience and journey of survival

The cornerstone of the relationship between Aboriginal and Torres Strait Islander People and Country is…

Reciprocity

Carl Linnaeus

A Swedish philosopher who lived in the 1700s who proposed a system for organising plants and animals into a classification based on similarities

Linnaean Classification includes 2 parts…

Binomial nomenclature and hierarchical classification

How do we hierarchically classify organisms?

Class, infraclass, superorder, order, family, subfamily, tribe, genus, subgenus, species, subspecies

Hierarchical classification is like…

A postal address for understanding where a species ‘belongs’ with the Linnaean taxonomic system

A taxon (plural taxa) is…

A named taxonomic unit in any level of the hierarchy - species, genus, family, etc.

Homology

Similarity arising from common ancestry

Homologous Traits

Traits that indicate shared ancestry

Analogy

Similarity arising from convergent evolution

Analogous Traits

Traits that are considered convergent

Convergent Evolution

Similar environmental pressures and natural selection produce similar adaptations in organisms from different evolutionary lineages

Species Meaning (Latin)

‘Kind’ or appearance

Offspring (in the context of life history traits)

How often an organism needs to reproduce and in what numbers

Parental Care

How much care is needed to ensure offspring survival

Reproductive isolation leads to…

Speciation and evolution (eg. galapagos finches evolving different beak shapes)

Macroecology and biogeography help us understand…

The relationships between organisms and the environment

The main driving force behind the world’s climate is…

A basic imbalance of energy

Inter-Tropical Convergence Zone (ITCZ)

A belt of low pressure around the equator where winds converge from the Northern and Southern hemispheres coming together

Australian Seasons (10-45 degrees south)

In summer, high pressure cells move towards the South Pole - In winter, high pressure cells move towards the Equator

How do Hadley Cells change with the seasons?

The centre of Hadley Cells change latitude with the seasons

What drives global climate?

The thermal equator moves from North to South with the seasons because of the tilt on the earth’s axis

High Pressure Belt

A belt of descending high pressure air over subtropical regions (approx. 30 N and 30 S of equator)

Oceanic Circulation and Trade Winds

Surface air moves back towards the equatorial trough formed by Hadley Cells, gaining moisture over water and descending on land

Orographic Rainfall

Local topography interacts with global scale tropospheric circulation to create localized climate patterns, creating local terrestrial biomes, regional ecosystems, and drainage patterns

Australian Orographic Rainfall

A main divide that causes orographic rainfall in eastern Australia - Tasmania also gets orographic rainfall in the west from Antarctic air

Climatograph

Plots annual precipitation against temperature, strongly correlates with the vegetation type of the region(s)

Abiotic factors (other than climate) that shape the distribution of terrestrial biomes

Geomorphology (soils and topography), fire regimes, salinity, sunlight, pathogens, and human induced disturbances