Phylum Mollusca

Characteristics of Mollusks:

Characteristics of Mollusks: soft bodied

soft bodied

Characteristics of Mollusks: soft bodied some have shells and some do not

soft bodied

some have shells and some do not

Snail

Slugs

Characteristics of Mollusks: soft bodied some have shells and some do not first organism on earth with complete organ system

soft bodied

some have shells and some do not

first organism on earth with complete organ system

Characteristics of Mollusks: soft bodied some have shells and some do not first organism on earth with complete organ system a coelom

soft bodied

some have shells and some do not

first organism on earth with complete organ system

a coelom

Characteristics of Mollusks: soft bodied some have shells and some do not first organism on earth with complete organ system a coelom two body openings (mouth & anus)

soft bodied

some have shells and some do not

first organism on earth with complete organ system

a coelom

two body openings (mouth & anus)

Clams

Characteristics of Mollusks: soft bodied some have shells and some do not first organism on earth with complete organ system a coelom two body openings (mouth & anus) all have a special organ called a mantle

soft bodied

some have shells and some do not

first organism on earth with complete organ system

a coelom

two body openings (mouth & anus)

all have a special organ called a mantle

The Mantle:

The Mantle: thin membrane surrounding internal organ

thin membrane surrounding internal organ

The Mantle: thin membrane surrounding internal organs secretes the shell material if there’s a shell

thin membrane surrounding internal organs

secretes the shell material if there’s a shell

Habitat:

Habitat: most are marine, some in freshwater

most are marine, some in freshwater

Habitat: most are marine, some in freshwater few on land (only in moist environments)

most are marine, some in freshwater

few on land (only in moist environments)

Mollusk Diversity

Mollusk Diversity Three main classes of mollusks:

Three main classes of mollusks:

Mollusk Diversity Three main classes of mollusks: Bivalves

Three main classes of mollusks:

Mollusk Diversity Three main classes of mollusks: Bivalves Gastropods

Three main classes of mollusks:

Mollusk Diversity Three main classes of mollusks: Bivalves Gastropods Cephalopods

Three main classes of mollusks:

Bivalves

Bivalves two shells

two shells

Bivalves two shells no distinct head

two shells

no distinct head

Bivalves two shells no distinct head filter feeders

two shells

no distinct head

filter feeders

Clamming on the Beach in Oregon

Giant Clams

Scallop

Mussels

Abyssal threads on a mussel

Oyster with Pearl

Gastropods (“stomach foot”)

Gastropods (“stomach foot”) one shell or no shell

one shell or no shell

Gastropods (“stomach foot”) one shell or no shell simple nervous system with small brain

one shell or no shell

simple nervous system with small brain

Gastropods (“stomach foot”) one shell or no shell simple nervous system with small brain only mollusk found on land

one shell or no shell

simple nervous system with small brain

only mollusk found on land

Gastropods (“stomach foot”) one shell or no shell simple nervous system with small brain only mollusk found on land most terrestrial ones are hermaphrodites

one shell or no shell

simple nervous system with small brain

only mollusk found on land

most terrestrial ones are hermaphrodites

Gastropods (“stomach foot”) one shell or no shell simple nervous system with small brain only mollusk found on land most terrestrial ones are hermaphrodites snails, slugs, abalone, chitons, limpets

one shell or no shell

simple nervous system with small brain

only mollusk found on land

most terrestrial ones are hermaphrodites

snails, slugs, abalone, chitons, limpets

Pacific Northwest Banana Slug

All gastropods have a mouth with Radula

Nudibranchs – poisonous sea slugs

Abalone

Chiton

Chiton on Rock

Chiton

Limpets

Cephalopods (“head foot”)

Cephalopods (“head foot”) the most complex and most recently evolved of all the mollusks

the most complex and most recently evolved of all the mollusks

Cephalopods (“head foot”) the most complex and most recently evolved of all the mollusks most complex nervous system of all invertebrates (highly organized brain)

the most complex and most recently evolved of all the mollusks

most complex nervous system of all invertebrates (highly organized brain)

Cephalopods (“head foot”) the most complex and most recently evolved of all the mollusks most complex nervous system of all invertebrates (highly organized brain) all have complex eyes that see images

the most complex and most recently evolved of all the mollusks

most complex nervous system of all invertebrates (highly organized brain)

all have complex eyes that see images

Cephalopods (“head foot”) the most complex and most recently evolved of all the mollusks most complex nervous system of all invertebrates (highly organized brain) all have complex eyes that see images propel themselves backwards with jets of water

the most complex and most recently evolved of all the mollusks

most complex nervous system of all invertebrates (highly organized brain)

all have complex eyes that see images

propel themselves backwards with jets of water

Cephalopods (“head foot”) the most complex and most recently evolved of all the mollusks most complex nervous system of all invertebrates (highly organized brain) all have complex eyes that see images propel themselves backwards with jets of water includes squid, octopuses, the chambered nautilus

the most complex and most recently evolved of all the mollusks

most complex nervous system of all invertebrates (highly organized brain)

all have complex eyes that see images

propel themselves backwards with jets of water

includes squid, octopuses, the chambered nautilus

Nautilus shell (the only shelled cephalopod)

Nautilus Eating a Crab

Squid

Giant Squid (7 meters long)

Octopus

Squid & Octopus Defense:

Squid & Octopus Defense: ink to distract predators

ink to distract predators

Squid & Octopus Defense: ink to distract predators most complex form of camouflage of any animal

ink to distract predators

most complex form of camouflage of any animal

Squid & Octopus Defense: ink to distract predators most complex form of camouflage of any animal intelligence ???

ink to distract predators

most complex form of camouflage of any animal

intelligence ???

Octopus camouflage: http://www.youtube.com/watch?v=5rqhomPaxhE&feature=related http://www.youtube.com/watch?v=JJq-wAUmkeg

Is the octopus “intelligent”? http://www.youtube.com/watch?v=T8cf7tPoN5o