Topic 4: Variation: Species and Taxonomy

Species – group of similar organisms with similar features with same genes/chromosomes

Two members of a species would be able to reproduce to produce fertile offspring

Why is courtship useful?

• Ensures correct species mate (prevents wasteful inter-species breeding) → Successful meeting, production fertile, offspring and raising of offspring

• Ensures correct gender

• Ensures ready to meet (production gametes etc) → Maximises chance of successful reproduction, like in species where females only produce egg cells at specific times to determine if the female is at the receptive stage of mating

• Increases chances of successful pairing

• Reduces wasted “energy” and resources

Examples of courtship

Behaviours like flashing light patterns in fireflies or butterfly chemical signalling displaying uniqueness to species that only the correct species respond to

Taxonomy

Hierarchical Taxonomic system

Carl Woes

Domain: Archae, Prokaryota, Eukaryota

Classification organisers organisms into groups based on similarities

This allows scientist to:

• Identify new species

• Study evolutionary relationships

• Understand shared traits and adaptations

• Share research globally to identify links with organisms on other continents

Carl Linnaeus

Kingdom, phylum, class, order, family, genus, species – eight major taxonomic ranks used to classify organisms

Taxonomic groups

Taxons are smaller groups within taxonomic groups e.g. birds and fish

Taxonomy

The process of putting animals into these groups

Hierarchy

Smaller groups placed within larger groups. Non-overlapping e.g. not vertebrae and invertebrate. Hierarchy is often based on evolutionary relationships

Three domains that animals can be classified into

1. Archaea

2. Bacteria

3. Eukarya

Eukarya includes four different kingdoms

1. Plantae (plants)

2. Animalia (animals)

3. Protictista (unicellular eukaryotes)

4. Fungi (such as yeasts)

Using binomial nomenclature

I know your naming system gives each species a two part ‘binomial’ Latin name. The binomial name is italicised when typed and underlined when written down. this avoids confusion from regional common names for organisms

The name consists of

1. The genus - This has an uppercase first letter

2. The species - This is all lowercase

E.g. Homo sapiens and Canis Familiaris

Adaptations

Adaptations are inherited characteristics that enhancing organisms ability to survive and reproduce in its specific environment

The three adaptation categories are

1. Anatomical – physical structures, both internal and external

2. Behavioural – activities and responses, whether inherited or learnt

3. Physiological – internal biological functions

It is common for adaptations to span several categories. For example, a peacock displaying its colourful tail feathers during meeting rituals showcases both anatomical and behavioural adaptations.

Anatomical adaptations – are the physical attributes that aid an organisms survival

• Body Covering – fur, feathers, scales that protect organisms and support their survival

• Camouflage – organisms with colouration that blends into their environment are less slightly to be detected

• Mimicry – some species imitate the appearance of more dangerous ones for protection

• Teeth – the shape of them are adapted to its diet

Behavioural adaptations – our actions that increase in organisms, chances of survival and reproduction

• defence responses – e.g. opossums Playdead and rabbits freeze to avoid detection by predators

• Courtship displays – e.g. male scorpions dance to attract mates

• Seasonal actions – e.g. migration helps birds access resources year-round and hibernation helps bears conserve energy when food is scarce

Physiological adaptations – our internal processes that give organisms an edge in survival

• Venom – used by snakes to immobilise prey and plants to deter herbivores

• Antibiotics produced by bacteria to compete rival species

• Water storage – desert frogs can survive for over a year without a water source by storing water in their bodies