Classification
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
Why classify organisms?
Blue whale - MAMMAL
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
Emperor penguin - BIRD
Dusky dolphin - MAMMAL
Classification
• Linnaean classification
– Genus and species, e.g. Homo sapiens
Panthera leo
Panthera tigris
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
– Bacteria
– Fungi
– Plants
– Animals
(e.g. amoebae, algae)
(e.g. bacteria, archaebacteria)
Classification
Kingdom Animalia
• ~ 1.26 million animal species
• Vertebrates and invertebrates
• ~ 1.2 million are invertebrates
(e.g. insects, crustaceans)
Monarch butterfly
INVERTEBRATE
• ~ 60,000 are vertebrates
Great white shark VERTEBRATE
Classification
INVERTEBRATES
• No spinal column (also called backbone)
• No internal skeleton
VERTEBRATES
• Have a spinal column
• Have an internal skeleton
Seven-spot ladybird
INVERTEBRATE
Vertebrates are divided into five groups:
• Fish
• Amphibians
• Reptiles
• Birds
• Mammals
Purple frog
VERTEBRATE
The Vertebrates
Mammals
• Produce milk from
mammary glands to
feed young
• Maintain constant body
temperature (warmblooded)
• Covering of hair
• Give birth to live young
The Vertebrates
irds
• Maintain a constant body
temperature (warmblooded)
• Reproduce by laying eggs
• Have feathers
• Most can fly
• Have a beak
The Vertebrates
Reptiles
• Don’t regulate body
temperature (cold-blooded)
• Tough scaly skin
• Most lay eggs with leathery
shells
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
The Vertebrates
ish
• Actually 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)