1. Classification

2. Classification What is classification?
Organising living things into groups:
Anatomy
Genetics
Horseshoe crab
Anatomically - looks like a crab
Genetically - more closely related to spiders
Classification is the process by which we put organise living things into groups according to their features.
In the past this was mostly based on anatomy (what a species looks like). Now we can classify species based on a number of features, most importantly a species’ genetics (genes, the code that determines your inherited characteristics) and how closely related species are genetically.
For example, the horseshoe crab looks like a crab. However, genetically it is related to arachnids – spiders, scorpions, ticks and mites. Genetics can reveal more than anatomy about how we should classify species.

3. Why classify organisms?
Classification
Why classify organisms?
Explore what the class already knows about classification and why we classify organisms.
Blue whale is a mammal – classifying species helps us
Blue whale - MAMMAL

4. Classification Why classify organisms?
Helps others understand which species you are talking about
Can group species based on shared characteristics
To study phylogeny – how related species are
We classify organisms for the same reason we classify things in our everyday life – it means we can generalise between the tens of millions of possible species on the planet, by putting them into categories.
It helps others know what you are talking about when you refer to them – for example – the word “mammal”, makes people think of a furry, warm-blooded, animal.
Classification is also important in phylogeny – the study of the evolutionary history of species. By studying the similarities and differences between species, we can get a good idea of how related they are and perhaps the order in which they evolved.
Emperor penguin - BIRD
Dusky dolphin - MAMMAL

5. Classification Linnaean classification
Genus and species, e.g. Homo sapiens
Panthera leo
Panthera tigris
There are a few methods for classifying organisms. The method that most people use is Linnaean classification. In science, Latin is used as a universal language that anyone from around the world can understand. In Latin names, the first word is the genus and the second is the species.
For example – the lion and the tiger are different species but they are closely related. They are known as Panthera leo and Panthera tigris. As they both have the same genus name – Panthera – we can tell that they are closely related. The species names – leo and tigris – show that they are different species.

6. Classification Genus and species are the tip of the iceberg
There are many different levels in the classification hierarchy
Top level is the 5 Kingdoms:
Protists (e.g. amoebae, algae)
Prokaryotes (e.g. bacteria, archaebacteria)
Fungi
Plants
Animals
Genus and species are the tip of the iceberg. There are many different levels in the classification hierarchy. The levels are:
Kingdom
Phylum
Class
Order
Family
Genus
Species
The top level in the classification hierarchy is “Kingdom”. The five Kingdoms are:
Protists
Prokaryotes
Fungi
Plants
Animals
This presentation concentrates on the classification of animals.

7. Classification Kingdom Animalia ~ 1.26 million animal species
Vertebrates and invertebrates
~ 1.2 million are invertebrates
(e.g. insects, crustaceans)
~ 60,000 are vertebrates
Monarch butterfly INVERTEBRATE
In the Kingdom Animalia there are around 1.26 million described animal species. These species are divided into vertebrates and invertebrates.
There are around 60,000 described vertebrates and 1.2 million described invertebrates.
Great white shark VERTEBRATE

8. Classification INVERTEBRATES No spinal column (also called backbone)
No internal skeleton
VERTEBRATES
Have a spinal column
Have an internal skeleton
Vertebrates are divided into five groups:
Fish
Amphibians
Reptiles
Birds
Mammals
Seven-spot ladybird INVERTEBRATE
Invertebrates don’t have a spinal column (backbone) or an internal skeleton.
Vertebrates have a spinal column and an internal skeleton.
Vertebrates are divided into five groups – also called CLASSES – fish, amphibians, reptiles, birds and mammals.
Purple frog VERTEBRATE

9. The Vertebrates Mammals
Produce milk from mammary glands to feed young
Maintain constant body temperature (warm-blooded)
Covering of hair
Give birth to live young
Key characteristics of mammals.
There are exceptions to the rules:
Some mammals do not have a covering of hair e.g – whales ( dolphins ( and porpoises (
Some mammals do not give birth to live young – echidna ( and platypuses ( lay eggs

10. The Vertebrates
Birds
Maintain a constant body temperature (warm-blooded)
Reproduce by laying eggs
Have feathers
Most can fly
Have a beak
Key characteristics of birds.
There are exceptions to the rules:
Some birds cannot fly e.g. penguins ( emus ( ostriches (

11. The Vertebrates Reptiles
Don’t regulate body temperature (cold-blooded)
Tough scaly skin
Most lay eggs with leathery
shells
Key characteristics of reptiles.
There are exceptions to the rules:
Although most reptiles lay eggs some, such as the adder ( and viviparous lizard ( give birth to live young.

12. The Vertebrates Amphibians
Don’t regulate body temperature (cold-blooded)
Lay eggs in water
Life cycle involves transformation from aquatic larvae to terrestrial adult
Can respire through porous skin
Key characteristics of amphibians.
There are exceptions to the rules:
Some amphibians, such as the axolotl ( don’t complete their life cycle. Instead, they remain in a larval state.

13. The Vertebrates Fish A collection of four distantly related groups
Breathe underwater using internal gills for gas exchange
Body covered with scales
Most don’t regulate body temperature (cold-blooded)
Key characteristics of fish.
The four related groups of fish are hagfish, lampreys, cartilaginous fishes and bony fishes.
There are exceptions to the rules:
Although most fish don’t regulate body temperature (they are cold-blooded) – some sharks, such as the great white shark ( can regulate their body temperature.

14. Activity 1: Guess Zoo Vertebrates Get into groups of 6 - 8
Take a species card - DO NOT LOOK AT IT!
Hold the card on your head for the rest of your group to see
Take turns to ask Yes or No Questions to work out which animal you are
Ask questions based on classification
e.g. do I have cold blood?
Note: Asking if you are a mammal, bird, reptile, amphibian or fish is against the rules!

15. Activity 2: Insect classification
Invertebrates
Activity 2: Insect classification
Insects are probably the most successful of all invertebrates.
All insects have:
An external skeleton
A body split into three segments – head, thorax and abdomen
Six jointed legs, one pair on each body segment
Antennae
Insects are probably the most successful of all invertebrates. They are among the most diverse groups of animals on the planet.
There are over a million described species of insect.
Over half of all known living organisms are insects.
Key characteristics of insects:
- An external skeleton
- A body split into three segments – head, thorax and abdomen
- Six jointed legs, one pair on each body segment
- Antennae

16. Activity 2: Insect classification
Invertebrates
Activity 2: Insect classification
Most insects have:
2 or 4 wings for all or part of their life
Compound eyes
Other characteristics of most insects:
2 or 4 wings for all or part of their life
Compound eyes

17. Activity 2: Insect classification
Invertebrates
Activity 2: Insect classification
Use a computer to research the following insect orders:
Coleoptera, Hymenoptera, Lepidoptera, Diptera, Odonata
Using for inspiration, draw a typical species of 1 or 2 of these groups on A3 paper
Label the diagram with the defining features of the insect order it belongs to
Insects can be divided into 29 major groups called orders. The insects in each order share similar characteristics.
Ask the students to research into some of the insect orders to find out what makes each order different from the others.
Using a computer to access ARKive, students should research the defining characteristics of the following insect orders:
Coleoptera
Lepidoptera
Odonata
Hymenoptera
Diptera
Hint: students should think about the characteristics that define an insect and look at what makes insects from different orders look different. For example, how do the wings differ?
Ask the students to choose one or two orders from the five above and draw an example of an insect from each. Students can use the images on ARKive to help them.
Ask the students to label the features of the insects they have drawn, paying particular attention to the features that make each order different from the other orders.

18. Grasshoppers and crickets
Orthoptera -
Grasshoppers and crickets
Stridulation – rubbing wings/legs/abdomen to create sound
Wings folded over abdomen
Large eyes
Ovipositor
Example of an insect order: Orthoptera, which includes grasshoppers and crickets
Ears in legs or abdomen
Incomplete metamorphosis

19. Discussion questions Why do we classify organisms?
What are the defining characteristics of mammals?
What are the defining characteristics of insects?
Ask the class to discuss what they have learnt about classification. Example questions:
Why do we classify organisms?
We can generalise between the tens of millions of possible species on the planet, by putting them into categories.
It helps others know what you are talking about when you refer to them.
Classification is also important in phylogeny – the study of the evolutionary history of species. By studying the similarities and differences between species, we can get a good idea of how related they are and perhaps the order in which they evolved.
What are the defining characteristics of mammals (or birds / reptiles / amphibians / fish)?
Mammals:
- Nourish young on milk from mammary glands
- Maintain constant body temperature (warm-blooded)
- Covering of hair
- Normally give birth to live young
What are the defining characteristics of insects?
All insects have:
- An external skeleton
- A body split into three segments – head, thorax and abdomen
- Six jointed legs, one pair on each body segment
- Antennae