Name:

Biology 11 Enriched: Kingdom Animalia OverviewIntroduction: This overview of Kingdom Animalia is in preparation for the class field trip to the

Vancouver Aquarium. It will focus on:

a) The evolution of complexity in the Kingdom Animalia.

b) The distinctive features of each phyla.

Kingdom Protista (Amoebas and others)

-Kingdom Protista are a catch-all category for all eukaryotic organisms that are not animals, plants or fungi.

-Protists were the first eukaryotes to evolve. They did so by Primary Endosymbiosis.

-Protists can be unicellular or exist in colonies and it is the latter that is thought to have given rise to Kingdom Animalia (Kingdoms Plantae and Fungi as well).

-What does it mean to be “colonial”?

-Cells that live together, but still individually have to perform all necessary life functions.

Phylum Porifera (Sponges)

-Porifera means ‘pore-bearing’

-Sponges are the most ancestral members of Kingdom Animalia and, as such, are evolutionary less complex in terms of the traits they possess.

-However, sponges should not be thought of as ‘primitive’ as they are very successful in their niche.

-Sponges are ecologically valuable as filter feeders and habitat for other organisms. Scientifically, sponges produce a variety of antibiotics and other defensive compounds that are useful.

Evolutionary Traits/Complexity Phylum PoriferaLevel or Organization -Multicellular

Symmetry -AsymmetricalNervous System and Cephalization -None

Skeleton and Movement -Spicules of Calcium Carbonate, Silica or Spongin-Motile larvae; Sessile adults

Digestion -Filter feedersExcretion -No specialized system, relies on the movement of water and

diffusionCirculation -No specialized system, relies on the movement of water and

diffusion-Amoebocytes transport nutrients internally

Respiration - No specialized system, relies on the movement of water and diffusion

Reproduction - Asexual (fragmentation, budding) and Sexual (broadcast spawning)

Phylum Cnidaria (Jellyfish, Sea Anemones, Coral)

-Cnidaria means ‘nettle’.

-Cnidarians were the first animals to possess tissues. They have both a nervous system and muscle tissues, which work together with the hydrostatic skeleton to permit movement.

-Cnidarians were also the first organisms to have two germ layers in the developing embryo (endoderm and ectoderm) and possess an inert, jelly-like layer (mesoglea) between the two.

-All Cnidarians have cnidocytes (stinging cells) that contain nematocysts, which shoot out like harpoons into prey. Nematocysts secrete toxins into prey, paralyzing them.

Evolutionary Traits/Complexity Phylum CnidariaLevel or Organization -Tissue

Symmetry -RadialNervous System and Cephalization -Nerve Net

Skeleton and Movement -Muscles and hydrostatic skeletonDigestion -Gastrovascular cavityExcretion -No specialized system, relies on the movement of water and

diffusionCirculation -No specialized system, relies on the movement of water and

diffusionRespiration - No specialized system, relies on the movement of water and

diffusionReproduction - Asexual (budding) and Sexual (broadcast spawning)

Phylum Platyhelminthes (Flatworms)

-Platyhelminthes means ‘flatworm’.

-Flatworms were the first organisms to have: Bilateral symmetry, cephalization, organs, a mesoderm (germ layer between the endo and ecto-derm), and a proto-kidney to deal with metabolic waste and to be acoelomate.

-Flatworms can be free-living or

parasitic.

Evolutionary Traits/Complexity Phylum PlatyhelminthesLevel or Organization -Organ

Symmetry -BilateralNervous System and Cephalization -Ganglia form a simple brain

-Cephalization (sensory organs on anterior end of body)Skeleton and Movement -Muscles and hydrostatic skeleton

-Mucus and cilia in planariaDigestion -Gastrovascular cavityExcretion -Relies on the movement of water and diffusion.

-Metabolic wastes pushed out of body by protonephridia (flame cells)

Circulation -No specialized system, relies on the movement of water and diffusion

Respiration - No specialized system, relies on the movement of water and diffusion

Reproduction - Asexual and Sexual (hermaphroditic; internal fertilization)

Phylum Nematoda (Nematodes)

-Nematoda means ‘thread’.

-Nematodes were the first animals to have a pseudocoelom and a tube-within-a-tube body plan (separate mouth and anus) The later permitted a complete digestive tract with specialization of its different parts to exist.

-Free living nematodes are important decomposers. Parasitic nematodes cause diseases in humans and other animals.

Evolutionary Traits/Complexity Phylum NematodaLevel or Organization -Organ

Symmetry -BilateralNervous System and Cephalization -Ganglia form a simple brain

-CephalizationSkeleton and Movement -Muscles and hydrostatic skeleton

Digestion -Tube-within-a-tube body plan = complete digestive tractExcretion -Excretion through the anus

-DiffusionCirculation -No specialized system, relies on diffusionRespiration - No specialized system, relies on diffusion

Reproduction - Sexual (Separate genders; internal fertilization)

Phylum Mollusca (Bivalves, Cephalopods, Gastropods, Chitons)

-Mullosca means ‘soft bodied’.

-All Molluscs are made up of three basic body parts:

a) Muscular foot, which can be modified for many different purposed and ways of moving.

b) Visceral Mass, which contains the internal organs.

c) Mantle, the fold of tissue covering the visceral mass and which secretes the shell.

-Molluscs have a radula. This fleshy tongue is covered with tough ‘teeth’ and used to rasp food sources.

-Many Molluscs have an external shell, but in some this has become internal or lost completely.

Evolutionary Traits/Complexity Phylum MolluscaLevel or Organization -Organ

-SegmentationSymmetry -Bilateral

Nervous System and Cephalization -Simple (Bivalves)-Complex (Cephalopods)

Skeleton and Movement -External, internal or no shell-Muscular foot-Mucous-Jet propulsion (Cephalopods)

Digestion -Tube-within-a-tube body plan = complete digestive tract-Radula

Excretion -Excretion through the anus

-Nephridia (Kidney) removes ammoniaCirculation -Open or closed systemRespiration -Gills (Aquatic) or lungs (Terrestrial)

Reproduction - Sexual (Internal or external fertilization)

Phylum Annelida (Earthworms, Leeches, Bristle Worms)

-Annelida means ‘little rings’ and reflects that these animals have a segmented body plan.

-Annelida were the first animals to possess a true coelom

-Bristles are grouped together in marine worms to form parapodia.

Evolutionary Traits/Complexity Phylum AnnelidaLevel or Organization -Organ

-SegmentationSymmetry -Bilateral

Nervous System and Cephalization -Brain and several nerve cordsSkeleton and Movement Hydrostatic skeleton and muscles

Digestion -Tube-within-a-tube body plan = complete digestive tract with specialization

Excretion -Excretion through the anus-Nephridia

Circulation -ClosedRespiration -Moist skin (terrestrial or gills (aquatic)

Reproduction - Sexual (Hermaphroditic)

Phylum Arthropoda (Insects, Crustaceans, Spiders, Trilobites, Myriapods)

-Arthropoda means ‘jointed legs’.

-Arthropods are the most numerous animal phyla and currently account for 83% of all known species!

-All Arthropods have: Bilateral symmetry, segmented body, exoskeleton, jointed legs and many pairs of specialized limbs.

-Segmentation and many pairs have limbs have led to extensive specialization of different parts of the Arthropod body. These features have played a large role in their success.

Evolutionary Traits/Complexity Phylum ArthropodaLevel or Organization -Organ

-SegmentationSymmetry -Bilateral

Nervous System and Cephalization -Brain and well developed nervous systemSkeleton and Movement -Exoskeleton and muscles

Digestion -Tube-within-a-tube body plan = complete digestive tractExcretion -Excretion through the anus

-Malpighian tubulesCirculation -OpenRespiration -Trachae System or Book Lungs

Reproduction - Sexual (Internal or external fertilization)

Phylum Echinodermata (Seastars, Sand Dollars, Sea Urchins)

-Echinodermata means ‘spiky skin’.

-Echinoderms are unique in that they have a water vascular system that is involved in their movement, respiration and excretion.

-Echinoderms are deuterostomes, like Chordates. This means that the blastopore, the first opening in the developing embryo, becomes the anus.

Evolutionary Traits/Complexity Phylum EchinodermataLevel or Organization -Organ

-SegmentationSymmetry -Bilateral (larvae) and radial (adults)

Nervous System and Cephalization -Nerve ring-No cephalization

Skeleton and Movement -Internal skeleton-Water vascular system and tube feet

Digestion -Stomach is pushed out in some species to digest preyExcretion -Excretion through the anus

-Movement of water in water vascular systemCirculation -Water vascular systemRespiration -Water vascular system

Reproduction - Sexual (External fertilization)

Phylum Chordata (Fish, Amphibians, Reptiles, Birds, Mammals)

-All chordates share the following characteristics at one point in their life cycle:

a) Notochord

b) Dorsal Hollow Nerve Cord

c) Pharyngeal slits

d) Post-Anal Tail

-Phylum Chordata shows the transition from invertebrates living in the ocean to craniates with vertebrae capable of living fully out of the water and in many different habitats.

Evolutionary Traits/Complexity Phylum EchinodermataLevel or Organization -Organ

-SegmentationSymmetry -Bilateral

Nervous System and Cephalization -Central nervous systemSkeleton and Movement -Internal skeleton and muscles

Digestion -Tube-within-a-tube = complete digestive systemExcretion -Excretion through the anus

-Kidneys.Circulation -ClosedRespiration -Lungs, gills or skin

Reproduction - Sexual (Internal or external fertilization)