Upload
amanda-sparks
View
220
Download
1
Tags:
Embed Size (px)
Citation preview
IntroductionIntroduction
More than a million artrhopods More than a million artrhopods have been identified to date.have been identified to date.
More have yet to be discoveredMore have yet to be discovered
Unbelievable diversity of animalsUnbelievable diversity of animals
SubphylaSubphyla
Subphylum ChelicerataSubphylum Chelicerata – – spiders, ticks, mites , scorpions, spiders, ticks, mites , scorpions, and horseshoe crabsand horseshoe crabs
Subphylum MandibulataSubphylum Mandibulata Class CrustaceaClass Crustacea – crabs, lobster, – crabs, lobster,
shrimpshrimp ClassClass DiplopodaDiplopoda – Millipedes – Millipedes ClassClass ChilopodaChilopoda – Centipedes – Centipedes ClassClass InsectaInsecta - Insects - Insects
Body Plan:Body Plan:
Exoskeleton made of chitinExoskeleton made of chitin Provides protectionProvides protection Waterproof – restricts water lossWaterproof – restricts water loss
Head, abdomen, thoraxHead, abdomen, thorax Some leathery – insectsSome leathery – insects Some hard – ticks, crabs, lobsterSome hard – ticks, crabs, lobster
FeedingFeeding:: Every method of feeding is represented by Every method of feeding is represented by
arthropodsarthropods Herbivores, carnivores, parasites, filter feeders Herbivores, carnivores, parasites, filter feeders
and detritus feedersand detritus feeders Some are specific, some (locusts) eat Some are specific, some (locusts) eat
anything greenanything green Some crabs and insects eat other live Some crabs and insects eat other live
animalsanimals Some eat animals and plants already dead Some eat animals and plants already dead External parasites, internal parasitesExternal parasites, internal parasites Filter feeders – barnacles Filter feeders – barnacles
RespirationRespiration::
3 types of respiration3 types of respiration 1.1. gillsgills 2.2. book gills and book lungsbook gills and book lungs 3.3. tracheal tubestracheal tubes
RespirationRespiration::
Book gills – Limulus , and book lungs Book gills – Limulus , and book lungs spiders are arranged like pages in spiders are arranged like pages in a booka book
–– more surface areamore surface area
Internal Transport:Internal Transport:
Well developed heartWell developed heart open circulatory system – some open circulatory system – some
vessels, but open into tissuesvessels, but open into tissues Blood moves into sinuses where it Blood moves into sinuses where it
collects and is returned to the collects and is returned to the heartheart
Excretion:Excretion:
Solid wastes leave through the anusSolid wastes leave through the anus Nitrogen wastes are removed in various Nitrogen wastes are removed in various
waysways These are bathed in blood inside body These are bathed in blood inside body
sinusessinuses The tubules remove wastes from the The tubules remove wastes from the
blood, concentrate it and then add it to blood, concentrate it and then add it to undigested food before it leaves the undigested food before it leaves the body body
Excretion:Excretion:
Aquatic arthropods – diffusion Aquatic arthropods – diffusion through unarmored places on the through unarmored places on the bodybody
Many aquatic arthropods (Lobster Many aquatic arthropods (Lobster for one) use a pair of “green for one) use a pair of “green glands” glands”
Response:Response: Most have well developed nervous systemsMost have well developed nervous systems all have a brain that consists of a pair of all have a brain that consists of a pair of
ganglia in the headganglia in the head Pair of nerves run around esophagus and Pair of nerves run around esophagus and
connect brain to spinal cord that runs connect brain to spinal cord that runs around ventral side of bodyaround ventral side of body
Several more ganglia, one for each body Several more ganglia, one for each body segment usually, coordinate movement of segment usually, coordinate movement of wings and legs. (That is why they can still wings and legs. (That is why they can still flap wings, or walk around after the head is flap wings, or walk around after the head is cut off) cut off)
Response:Response:
Compound eyes w/ as many as Compound eyes w/ as many as 2000 separate lenses2000 separate lenses
Can detect color and motion very Can detect color and motion very well – ever try to swat a fly?well – ever try to swat a fly?
Human eye vs. Insect eye Human eye vs. Insect eye Blades of a fan, UV lightBlades of a fan, UV light
Response:Response:
Sense and taste receptors (may be Sense and taste receptors (may be in strange places such as legs, or in strange places such as legs, or antennae)antennae)
Sensory hairs feel the movement Sensory hairs feel the movement of air or waterof air or water
May have well developed ears – May have well developed ears – eardrum in grasshopper is behind eardrum in grasshopper is behind the legs - can hear sounds the legs - can hear sounds humans can’t humans can’t
Protection:Protection:
ExoskeletonExoskeleton Can drop a claw or leg to get awayCan drop a claw or leg to get away Camouflage Camouflage
Movement:Movement:
well developed muscle systemswell developed muscle systems
generate force by contracting and generate force by contracting and transfer force to exoskeleton transfer force to exoskeleton
Reproduction:Reproduction:
Males and females produce sperm Males and females produce sperm and eggand egg
Fertilization occurs within the body Fertilization occurs within the body of the femaleof the female
Growth and Development:Growth and Development:
MoltingMolting Epidermis digests inner part of Epidermis digests inner part of
exoskeleton and absorbs much of exoskeleton and absorbs much of the chitinthe chitin
Secretes a new exoskeleton under Secretes a new exoskeleton under the old onethe old one
Growth and Development:Growth and Development:
Arthropod comes completely out of Arthropod comes completely out of its old exoskeletonits old exoskeleton
Commonly eats old exoskeleton, Commonly eats old exoskeleton, then grows then hardens – what is then grows then hardens – what is the first thing to harden in a the first thing to harden in a lobster molt? – mouthparts so it lobster molt? – mouthparts so it can eat the old exoskeleton can eat the old exoskeleton (recycle the chitin)(recycle the chitin)
Subphylum Subphylum ChelicerataChelicerata
spiders, ticks, mites , spiders, ticks, mites , scorpions, and scorpions, and
horseshoe crabshorseshoe crabs
Characteristics:Characteristics:
2 part body2 part body mouthparts called cheliceraemouthparts called chelicerae lack sensory “feelers” found on lack sensory “feelers” found on
other arthropodsother arthropods
Horseshoe Crabs:Horseshoe Crabs:
Limulus polyphemusLimulus polyphemus Not true crabsNot true crabs Over 430 million years oldOver 430 million years old Living fossilsLiving fossils 5 pr walking legs5 pr walking legs spikelike tailsspikelike tails up to 60 cm longup to 60 cm long