Presentation on theme: "Arthropods are different from all other animals because they are eucoelomates with a hard, segmented body. The phylum Arthropoda (jointed-foot) consists."— Presentation transcript:
1 Arthropods are different from all other animals because they are eucoelomates with a hard, segmented body. The phylum Arthropoda (jointed-foot) consists of most of the known animals and many are enormously abundant as individuals. The general characteristics of the arthropods include a hard exoskeleton called a cuticle made up of chitin and proteins. This hard exoskeleton gives the organism’s segmented body protection and a place for muscle attachment. Arthropods also have jointed appendages that allow for specialized functions. They have an organ system level or organization and they are triploblastic. There are five subphyla: Trilobita, Checlicerata, Crustacea, Myriapoda, and Hexapoda.
2 Subphylum: Trilobita This subphylum (like other arthropods) have pairedappendages.They are segmentedwithout any specialization.This subphylum are allextinct (Permian era –250 mya)
3 Subphylum: Cheliceriformes Cheliceriformes all have 6 pairs of appendages. The first pair is modified into chelicerae. The next pair are modified into pedipalps. The last 4 pairs are walking legs. These animals have one or two body regions (cephalothorax and abdomen). These animals do not have a mandible or any antennae.
4 Class: EurypteridsThe Eurypterids or water scorpions are animals that are now extinct. They were normally marine and freshwater predators.
5 Class: MerostomataThese organisms (horseshoe crabs) are found in shallow coastal waters. The first pair of appendages are modified into chelicerae but the second pair is not modified into pedipalps like other cheliceriformes. The Horseshow crab’s larvae look similar to the extinct trilobites.
6 Class: PycnogonidaThese organisms (sea spiders) are usually found in shallow coastal waters and many polar oceans. These animals often have eight legs (like true spiders) but may have extra legs from their segments being duplicated.
7 Class: ArachnidaThese organisms include spiders, scorpions, ticks, and mites. Spiders contain modified chelicerae which are used as fangs to inject poison. They also have a special gland that can produce silk used for webs, eggs, escape, and courtship. Scorpions are the first terrestrial invertebrates. Their pedipalps are modified into pinchers and their tail is modified into a stinger. Ticks and mites are parasitic.
8 Subphylum: CrustaceaCrustacea have two pair of antennae. Each appendage is biramous (two main branches). They have mandibles. These animals have two or three body regions (cephalothorax and abdomen or head, thorax, and abdomen). These animals are mostly marine.
9 IsopodaThe isopods are the most diverse crustaceans. These animals are found in terrestrial, freshwater, and saltwater habitats.
10 DecapodaThe decapods include many of the familiar crustaceans. They are mostly aquatic species.
11 CopepodaThe copepods are animals that are among the most numerous members of the marine and freshwater plankton community.
12 CirrepediaBarnicles are animals that are exclusively marine, and tend to live in shallow and tidal waters, typically in erosive settings.
13 Subphylum: MyriapodaMyriapods all have appendages that are uniramous (one main branch). The body is long with a distinct head. The have one pair of antennae. These animals also have a mandible.
14 Class: ChilopodaThese organisms are centipedes. They have one pair of jointed legs per segment. They have poison claws and are predators.
15 Class: DiplopodaThese organisms are millipedes. They have two pair or jointed legs per segment. (Two segments have fused together). They are herbivores.
16 Subphylum: HexapodaHexapods all have 6 appendages, each pair are attached to a segment of the thorax. The body consists of a distinct head, thorax, and abdomen. They have one pair of antennae. These animals also have a mandible.
17 Class: InsectaInsects are the most diverse of all arthropods. They may have been the cause of angiosperm diversity. Know the orders that are demonstrated here.
18 Arthropoda Level of Organization Organ-system Tissue Layers TriploblasticDigestive SystemAlimentary Canal with modified mouth partsExcretory SystemNephridiaCirculatory SystemOpen system with heartRespiratory SystemSkin, gills, tracheae or book lungsNervous SystemDorsal brain with ring connected to ventral cordsBody CavityTrueAsexual ReproductionBudding in someSexual ReproductionUsually Dioecious
19 Phylum: Echinodermata The word Echinodermata means “spiny skin”. These animals demonstrate secondary radial symmetry as adults (evolved from bilateral symmetry back to radial symmetry) while the larvae stage still exhibits bilateral symmetry. They are probably more closely related to the vertebrates because of their deuterostome development. Unique to echinoderms is the water vascular system used for locomotion, feeding and food exchange.
20 Echinoderm Structures (P 126 Figure 7.100) Oral Side: Side with mouthArboral Side: side without mouthMadreporite: opening into water vascular systemAmbulacral Grooves: Radiating grooves that contain tube feetPedicellariae: pincer-like organs on surface (see compound microscope)Papillae: skin gills
21 Echinodermata Classes CharacteristicsExamplesAsteroideaPentaradial symmetrySea starsOphiuroideaBrittle starsEchinoideaDisk-shaped, no arms, spinesSea urchinHolothuroideaCucumber-shaped, no arms, no spinesSea cucumbersCrinoideaSessile, arms used for filter-feedingSea lillies
22 Class: AsteroideaSea stars have five arms that radiate from a central disc. They have an open ambulacral groove. The madreporite is on the aboral side. They contain both pedicellariae and dermal branchiae.
23 Class: OphiuroideaThey have five thin arms radiating from a central disc. They have a closed ambulacral groove. The madreporite is on the oral side. They do not have pedicellariae or dermal branchiae.
24 The Sea urchins have no arms but have five rows of tube feet The Sea urchins have no arms but have five rows of tube feet. They contain moveable spines. They have closed ambulacral grooves. They madreporite is on the aboral side. They contain pedicellariae and dermal branchiae. They have specialized jaw-like structures called an Aristotle’s lantern.Class: Echinoidea
25 Class: HolothuroideaSea cucumbers are soft bodied animals with ambulacral areas with tube feet. They have an internal madreporite. They have no pedicellariae or dermal branchiae.
26 The sea lilies are attached to the substrate with many branched arms The sea lilies are attached to the substrate with many branched arms. They have open ambulacral grooves. They have no madreporite, pedicellariae or dermal branchiae.Class: Crinoidea
27 Bipinnaria LarvaeThe larvae form is evidence that this phyla has evolved radial symmetry from a bilateral ancestor. The larvae form is used for dispersal.
28 Echinodermata Level of Organization Organ-system Tissue Layers TriploblasticDigestive SystemAlimentary canalExcretory SystemAbsentCirculatory SystemReduced if at allRespiratory SystemDermal branchiae, tube feet, respiratory treeNervous SystemNo brain, nerve ring with radial nervesBody CavityTrueAsexual ReproductionRegenerationSexual ReproductionDioecious
29 Phylum: Chordata The Phylum Chordata include animals that sometime in their life cycle have a notochord (for muscle attachment), a hollow dorsal nerve cord (to send nervous signals), pharyngeal slits (various functions) and a post-anal tail (movement). The three subphyla are Urochordata, Cephalochordata, and Vertebrata.
30 Subphylum: Urochordata The Tunicates or Sea Squirts contain only the pharyngeal slits as an adult. They are usually sessile and use the pharynx for filter feeding.
31 Subphylum: Cephalochordata The Lancelets contain all four chordate characteristics as an adult. They are usually found buried in the sand off our coast. They are considered to be the closest relative to vertebrates.
32 Subphylum: Vertebrata The Vertebrates are animals with backbones. They contain all four chordate characteristics as an adult with some modifications. They are free-living.
33 What is a Fish?Fish are aquatic vertebrates that are not a mammal, bird, or reptile (It isn’t a monophyletic group).There are the five major living groups of fish:Hagfish (jawless)Lamprey (jawless)Cartilaginous FishLobe-finned FishRay-finned Fish
34 Superclass: AgnathaThe agnatha are animals without jaws and most lack paired appendages. Hagfishes may also lack eyes and a stomach. They are scavengers that enter natural openings on living and dead fish and mammals. Hagfish find their prey by a sense of smell. Hagfish can secrete large quantities of slime or mucus and can tie themselves into a knot which can also help release the slime.
35 Superclass: AgnathaThe agnatha are animals without jaws and most lack paired appendages. The adult lamprey feeds by attaching its mouth to a fish, secreting an anticoagulant into the host, and feeding on the blood and tissues of the host.Lamprey swim upstream to spawn. They are called ammocoetes as larva and are found in burrows. The larva must go through a metamorphosis to become adults where the entire digestive system must be restructured.
36 Superclass: Gnathostomata This superclass contains jaws which evolved from skeletal supports of the pharyngeal slits.
37 Class: Chondrichthyes The class chondrichthyes all lack true bone and have a skeleton made of cartilage which is not a primitive characteristic. Their tough skin is covered with placoid scales. Males have a structure called claspers which aren’t seen in females.The two subclasses in this class are Elasmobranchii (the sharks, skates, and rays) and the Holocehphali (the ratfish)
38 Shark ReproductionMale and female sharks can easily be told apart. Male sharks have claspers which are extensions of the pelvic fins used to transfer sperm. There is also three different types of shark egg development. They are:Viviparity: the mother feeds the “babies” by a placentaOviparity: the mother deposits eggs in the oceanOvoviviparity: the eggs are retained in mom but without any nourishment from the mother.
39 Order: Selachiformes Great White Sharks The Great White Shark measures up to 20 feet and can weigh up to 4200 lbs. They usually eat large bony fish, smaller sharks, dolphins, seals, and sea lions. They are found in almost all coastal and offshore waters between 54 to 75 degrees F. The Great White has been labeled a “man eater” but in the last 100 years more people have been killed by dogs in the U.S. than this shark.
40 Order: Selachiformes Leopard Sharks The Leopard Shark measures up to 6.5 feet and can weigh up to 40 lbs. They usually eat bony fish, crustaceans, worms, and clams. They are found along the coast from Oregon to Baja California. The leopard shark is spotted as a juvenile in the shallows but usually lose their spots as they get larger and move to deeper water.
41 Order: Selachiformes Whale Sharks The Whale Shark is the largest fish in the ocean and measures up to 66 feet and can weigh up to 7500 lbs. They usually are filter feeders eating enormous amounts of plankton. They are found in along the coast from Oregon to Baja California. The Whale shark can filter 6000 liters of water an hour.
42 Order: Selachiformes Hammerhead Shark The Hammerhead shark measures up to 18 feet and can weigh up to 1000 lbs. They usually eat fish, rays, other sharks, cephalopods and crustaceans. They are found in tropical and subtropical waters along the shorelines. The shape of the head is thought to spread their receptors across a larger area making them 10 times more likely to detect prey.
43 Order: Batiformes Skates and Rays Both skates and rays are flat bottom-dwelling organisms.Skates have a tiny caudal fin with no stinging spines, each pelvic fin is divided into two lobes and lay egg cases.Rays have a slender whip-like tail with stinging spines, each pelvic fin contains one lobe and give live birth.
44 Broad SkateThe broad skate is known to grow to be just under a meter in length. It is a deep-water skate found in the central and northern Pacific ocean. They feed on mollusks, crustaceans and fishes.
45 Manta RayThe manta ray is the largest of the rays, with the largest known specimen having been about 7.6 m (about 25 ft) across. It ranges throughout all tropical waters of the world, typically around coral reefs. Manta rays are believed by some to have evolved from bottom-feeding ancestry, but have adapted to become filter feeders in the open ocean
46 GuitarfishThe guitarfish are mainly found in tropical and temperate waters, traveling in large schools. Most adult guitarfishes reach five or six feet in length. These fish are bottom feeders, preferring small crustaceans.
47 Order: Chimaeriformes Chimaeras Chimaeras differ from sharks in that their upper jaws are fused with their skulls; they have separate anal and urogenital openings; and they lack the many sharp and replaceable teeth of sharks, having instead a few large permanent grinding tooth plates. They are often called ratfish or rabbit fish. They are found in cold water often at great depths. The diet consists primarily of benthic invertebrates. The tooth plates are used to crush hard-bodied prey such as crabs, clams, and echinoderms.
48 OsteichthyesThe “Osteichthyes” all have a skeleton made of true bone. Their skin is covered with ctenoid scales. They also have an operculum (a hard covering over the gills), which helps them breathe without having to swim. They also have a swim bladder which helps the body create a neutral balance between sinking and floating. There are two classes in this group: the Class: Sarcopterygii, the Lobe-finned fish and the Class: Actinopterygii the Ray-finned Fish
49 Sarcopterygii – Lobe-finned Fish Subclass: Coelacanthimorpha Coelocanths are lobe-finned fish with the pectoral and anal fins on fleshy stalks supported by bones, and the tail is divided into three lobes. Coelacanths also have a special electroreceptive device called a rostral organ in the front of the skull, which probably helps in prey detection.Coelacanth populations have been found near Indonesia and South Africa. Coelacanths are opportunistic feeders, hunting cuttlefish, squid, snipe eels, small sharks, and other fish.
50 Sarcopterygii – Lobe-finned Fish Subclass: Dipnoi Lungfish are fresh water lobe-finned fish. Lungfish are best-known for retaining primitive characteristics, including the ability to breathe air, Today, they live only in Africa, South America, and Australia. African and South American lungfish are capable of surviving seasonal desiccation of habitats by burrowing into mud and estivating throughout the dry season. They have a diet of fish, insects, mollusks, worms, crustaceans, and plant material.
51 Infraclass: Holosteri In this infraclass, all of the fish are considered to be primitive fish. They are found in brackish conditions. They can use their swim bladders to obtain extra oxygen
52 Infraclass: Holosteri Order: Lepisoteriformes Gars inhabit fresh, brackish, and occasionally marine, waters of eastern North America, Central America, and the Caribbean islands. They have a swim bladder that opens to the pharynx that can function as a lung and most gars surface periodically to take a gulp of air, doing so more frequently in stagnant or warm water when the concentration of oxygen in the water is low
53 Infraclass: Holosteri Order: Amiiformes Amia's are also called Bowfin or Dog fish. Amia’s distribution is restricted to eastern North America. Amia's swim bladder functions much like a lung, allowing this fish to gulp air when dissolved oxygen levels become dangerously low in the weed beds where it lives.They are primarily fish eaters, although crayfish can make up a substantial proportion of the diet, and frogs are also consumed.