Archaea, Bacteria (single-celled organisms) and Eukarya (multi-cellular organisms)
Eukarya has many branches including Animals.
Animals: “multi-cellular life form that feeds on others, moves around for at least part of life and responds to stimuli”
Representatives of each of 35 lineages share common body-plan and evolutionary history.
By looking at main animal lineages, we can make sense of diversity and understand how animals evolved, and which adaptations have enabled success.
Systematics: study of diversification of organisms and relationships between them. Uses morphological, physiological and molecular techniques to infer evolutionary relationships.
Basics of how evolutionary relationships are constructed, scientifically.
Importance of the body plan and diversification of animal life into 35 major lineages.
2.1 Animal Body Plans II
Evolutionary relationships between major lineages and the diversification of animal life.
Bilateria > Protosomes > Lophotrochozoa
Colonial animals, units of colony zooids are interdependent clones.
Each zooid has crown of feeding tentacles, gut and gonads but are linked in complex web of living tissue relaying nutrients, waste and info around colony.
Division of labour - feeding and defensive zooids. One defender looks like a bird’s beak and the other a brush.
Chemicals from symbiotic bacteria protect bryozoans (some have key medical uses)
Originally lumped together with Ectoprocta, but slightly diff structure
No exoskeleton - curl tentacles inward rather than retract
Colony made of individual connected zooids.
Spend much of life attached to mouthparts of clawed lobsters
Weird sex life - adults produce either mature females or male “prometheus larva”
Creeps around to find female then disintegrates
Female lays one egg, feeds larva when hatches
Live in bodies of other sea animals but nature of relationship with…