Post on 20-Dec-2015
Kingdom Animalia
Kingdom Animalia
• Eukaryotic (Domain Eukarya)• All Multi-cellular (unlike Protists)• All Heterotrophic (unlike Plants)• No cell walls (unlike Fungi and Plants)• Sexual reproduction• Cells are organized into structurally-functional
tissues
Marine Animals Without A Backbone
• There are two major groups of animals: the vertebrates, which have a backbone, and the invertebrates, those without a backbone
• Of all the species of animals, ~97% are invertebrates!
Marine Animals Without A Backbone
• All major groups of invertebrates have marine representatives, and many are exclusively marine
• Other than insects – one of the few invertebrate groups to invade land – most animals are marine!– ~8/10ths of all organisms
are Arthropods!
if Facebook existed years ago…
Phylum Porifera
• Sponges are the simplest of all animals; best described as aggregations of specialized cells
• Sponges do not have true tissues or organs; cells are largely independent of one another
• All are sessile (non-mobile)• Porifera means “pore bearer”• NO body symmetry
Phylum Porifera
• Tiny pores, or ostia allow water to enter and circulate through a series of canals where plankton and other organic debris are filtered out and eaten
• Sponges are suspension feeders, animals that eat food particles suspended in the water column
• Filter feeders; they actively filter out food particles
Phylum Porifera
• Water is pumped into a feeding chamber lined with collar cells, or choanocytes
• Choanocytes have a flagella that generates a current, and a thin collar that traps food particles
• Food is then ingested within the cell
Phylum Porifera
• As sponges get larger, they need structural support
• Most have spicules, supporting structures of different shapes and sizes, made of silica or calcium carbonate
• Many also have a ‘skeleton’ of tough, elastic fibers made of a protein called spongin
Phylum Porifera
• Wandering cells, or amebocytes secrete the spicules and spongin
• Amebocytes also transport and store excess food particles, and can change into other cell types, quickly ‘repairing’ any damage to the sponge
• ~80% of food particles are engulfed and ingested by choanocytes; smaller particles, inc. bacteria and dinoflagellates are eaten by amebocytes
Sponges are filter-feeders
You are what you eat…
• The silica frustules of diatoms and other phytoplankton help make the glass spicules of sponges!
DiatomsSponge
Sponges are boring!
• A family of sponges known as boring sponges bore into shells by use of an enzyme produced by the amebocytes
• Sponge larvae settle onto wood and/or shells and create burrows where they will grow
Sponge worthy?
• Unlike most animals, many sponges reproduce asexually
• Branches or buds break off to form separate, but identical, sponges
• Like all animals, however, sponges also reproduce sexually– Specialized coanocytes or amebocytes produce
eggs and sperm– Sponge larvae is planktonic!
Phylum Cnidaria
• Cnidarians (phylum Cnidaria) are multi-cellular animals with tissues that perform specific functions
• Cnidarians include the sea anemones, jellyfish, coral, and their relatives
• Cnidarians have radial symmetry; in fact radial symmetry evolved in the Cnidarians!
Cnidarians are rad!
• Animals with radial symmetry look the same from all sides and have no head, front or back
• Instead have an oral surface (where mouth is) and aboral surface
Phylum Cnidaria
• Cnidarians have a centrally-located mouth surrounded by tentacles, slender, finger-like projections used to capture and handle food
• All possess stinging cells, or nematocysts• Nematocysts employ neurotoxins which
paralyze prey; 7-17 different types• The mouth opens up to a gut, with only one
opening
Nematocystshttp://www.youtube.com/watch?v=BpKKGB-
ivQo&feature=related
Phylum Cnidaria
• Cnidarians occur in two basic forms: a polyp, a sac-like attached form with its mouth and tentacles pointed upward, and a bell-like medusa, which resembles an upside-down polyp adapted to swimming
• Some Cnidarians have both polyp and medusa stages; others spend their entire lives as either a polyp or a medusa
Phylum Cnidaria, Class Hydrozoa
• The Hydrozoans are a class of very small, predatory Cnidarians which can be solitary or colonial in form
Class Hydrozoa, Order Siphonophora
• Within class Hydrozoa, lies the Order Siphonophora, the Siphonphores– Siphonophores consist of colonies of medusa-like
and polyp-like individuals, each specialized for a specific function
– Specialized features include a gas-filled float, tentacles lined with nematocysts, and digestive cells
– Very toxic!
Portuguese Man o’ War: a siphonophore
By-the-wind Sailors: a siphonophore
Physophora: my nemesis!
http://life.bio.sunysb.edu/marinebio/plankton.html
Actual size
Phylum Cnidaria, Class Scyphozoa
• The Scyphozoans (class Scyphozoa) include most of the common medusa-like ‘jellyfish’
• Larger than Hydrozoans• Short polyp stage; Long medusa-stage
NOAA
Phylum Cnidaria, Class Scyphozoa
• Scyphozoan polyps are very small and release juvenile medusa
• Adult medusa have a rounded body, or bell• Scyphozoans swim with rhythmic
contractions of their bell, but their swimming ability is limited– Planktonic!– Painful stings to swimmers
Phylum Cnidaria, Class Anthozoa
• The Anthozoans (class Anthozoa) include the corals, sea anemones, and sea fans
• Anthozoans lack a medusa stage and exist as solitary or colonial polyps
• Many corals excrete a skeleton of calcium carbonate, which forms reefs (‘reef-building corals’); very important for marine ecosystem
• Anthozoans can sting and ‘attack’ each other!
Class Anthozoa
http://webs.lander.edu/rsfox/invertebrates/aiptasia.html
Phylum Ctenophora
• The comb jellies, or ctenophores are exclusively-marine
• NO nematocysts (not Cnidarians); instead of stinging cells, ctenophores possess sticky cells, or colloblasts
• 8 rows of cilia; Ctenophore literally means “comb bearer”
• ‘Boom and bust’ population dynamics
Phylum Ctenophora
• Most species are bioluminescent• Voracious feeders on copepods, fish eggs,
crab larvae, shrimp larvae and other meroplankton
• Self-fertilizing hermaphrodites• Can double in size in 1 day!• Important secondary consumers
in Long Island estuaries
Peanut butter and jellyfish anyone?
• Ctenophores are increasing in LI estuaries
• During peak ctenophore abundance in Great South Bay (in 2006), one 2-minute plankton tow yielded over 3,700 individuals (543.1 individuals m-3)!
Ctenophores vs. Zooplankton 2009
Ctenophores on Long Island
Spring: Sea gooseberry Summer: Sea walnut Fall: Beroe ovata
Understanding my ctenophore research through Pac Man…
Bivalve larvae(ctenophore food)
Phytoplankton (clam food)
Ctenophore
Lots of ctenophores!!!
GAME OVER(for the hard clam)