Solved by a verified expert:Some sharks need to swim constantly in order to keep water flowing across their gillsfor gas exchange (Ram-breathers). At this aquarium you will find many sharks that do not need to keep swimmingand can rest along the bottom. Name one of these sharks and briefly describe its lifestyle into your notebook.Biology 1BAquarium of the Bay Field Trip – 20 Questions by Dr. McCray1Getting ThereThe Aquarium of the Bay is conveniently located next to PIER 39 at The Embarcadero and Beach Street in SanFrancisco’s Fisherman’s Wharf. The Aquarium is usually open 10am to 6pm Monday through Thursday, and 10am to7pm Friday through Sunday. You should receive one free student ticket (courtesy of the Aquarium’s Partners forHigher Education Program) from your instructor. Additional tickets can be purchased for $16.50 (adults) or $8(children ages 3-11 and seniors 65+). For the latest information on hours and tickets refer to the Aquarium of the Baywebsite: http://www.aquariumofthebay.com/If taking Public Transit, visit www.511.org to get directions. The F Line (MUNI) stops right across the street fromthe Aquarium entrance.These are Mapquest instructions assuming you are driving from Merritt College:Take I-580 W toward San Francisco/BerkeleyTake I-80 W toward San Francisco.From I-80 take the Fremont St exit. Keep right at the fork and follow signs for Folsom St.Turn left at Folsom Street.Turn left at The Embarcadero.Public parking facilities are available across from the main entrance at the PIER 39 garage. The garage is open 24hours a day, 7 days a week. Please note that Aquarium of the Bay does not validate parking, but many PIER 39restaurants do. The Parking Rate is $7 per hour without validation. If you validate your parking stub at one of thenearby stores or restaurants then you can get one hour discounted.BRING THIS HANDOUT AND YOUR LAB NOTEBOOK!Read through this entire handout before you arrive to the Aquarium, since completing the activities described willrequire that you look for many things on display at each of the various tank exhibits. The handout addresses fivegeneral topics:I. CHARACTERISTICS OF THE SAN FRANCISCO BAYII. INVERTEBRATESIII. FISHIV. UNIQUE ADAPTATIONS OF CHONDRICHTHYESV. TO EAT OR NOT TO EATI. CHARACTERISTICS OF THE SAN FRANCISCO BAYThe displays for this topic are located on the top floor not far from the Aquarium entrance.Activity/Question 1: Use the computer panel in the National Marine Sanctuary display to describe these SanFrancisco Bay characteristics. Write your descriptions in your laboratory notebook.Depth.Temperature.Size of Watershed.Visibility.II. INVERTEBRATESInvertebrates are “animals without backbones.” Almost 2 million identified species are invertebrates, accounting formore than 98 percent of the animal kingdom. They live in an incredibly diverse range of habitats both on land and inwater. Among the more recognizable marine and coastal invertebrates are octopus, squid, lobster, crabs, clams,scallops, starfish, sea worms, corals and anemones. While invertebrates are remarkably diverse animals, there are twobasic body plans. Those having radial symmetry (corals and anemones) are rounded bodies arranged around a centralmouth. These animals typically spend their lives in one place (sessile) and wait for food to come to them. Those havingbilateral symmetry are those with two halves that mirror each other, with a distinct front and back. Bilateral symmetrycharacterizes most invertebrates. They can have several pairs of eyes and other specialized organs that can smell, touchand taste. Crabs and squid are good examples of bilaterally symmetrical invertebrates. Biology 1BAquarium of the Bay Field Trip – 20 Questions by Dr. McCray2Echinoderms. The word "echinoderm" means "spiny skin" in Latin, as most of them have spines or bumpy, roughskin. Animals that belong to this Phylum include sea stars, sea urchins and sea cucumbers.Cnidarians. The word "cnidarian" means "stinging cells" in Latin, as most of the members of this group are able tosting and have tentacles. Animals that belong to this Phylum include sea anemones, jellyfish, and corals.Cnidarians have radial symmetry and a single body opening that serves as mouth and anus. There are two body forms,the medusa and the polyp. A polyp is almost plant-like in its form and is usually sessile, attached to the surface ofsomething hard (a rock, pier piling, or another animal). A sea anemone is a typical example of a cnidarian polypform. A medusa form describes a drifting or swimming (motile) bell shape. A typical example of a medusa is thejellyfish. Some cnidarians spend portions of their life cycle in both types of body forms.Arthropods. The word "arthropod" means "jointed appendage" in Latin, as they have legs that have joints. Arthropodsmake up the largest phylum of animals, with about one million known species and many more yet undiscovered. Toput things in perspective: of all the animals on Earth, three out of four are arthropods! Arthropods cangenerally be identified by the following characteristics: a segmented body; bilateral symmetry; jointed appendages;and a hard external skeleton or exoskeleton. The majority of marine arthropods are crustaceans (they belong to thesubphylum Crustacea). This group includes well known arthropods such as shrimp, crabs and lobsters, as well aslesser known animals such as copepods and krill (both important forms of plankton). The majority of arthropods atAquarium of the Bay include crabs and barnacles. These animals are highly adapted to living in the San Francisco Baybecause they can handle lower salinity water typical of an estuary such as the Bay, high currents, and murky water.Many of these animals have low profile bodies, so they can usually hide in the sand or mud, or live clinging to anotherobject such as a rock or a pier piling.Molluscans. The word "mollusca" means "soft bodied" in Latin. Animals that belong to this Phylum have soft bodiesoften protected by a hard shell. This group includes snails, mussels, clams, chitons and octopus.Activity/Question 2. Construct a table in your notebook listing the four major invertebrate groups describedabove. For each phylum list one representative you found in the aquarium, describe the habitat where you found it,whether it is sessile or motile, any activity you observe taking place, and any other interesting things of note aboutthat species.Table headings to include in your notebook. Leave plenty of space for your notes:Name (if available, if not thenYourSessile? Motile?Behaviordescribe the animal)DrawingSpecial Notes(optional)III. FISHBehavioral Adaptations: SchoolingSome schooling fish are on display in the first exhibit tank (circular display). However, you may find it easier toanswer these questions after you have seen the schooling behavior in the “Under The Bay” tanks, where there is moreroom for fish to swim.The word “fish” covers a huge diversity of animals that have been on Earth for more than 500 million years and rangein size from finger-length minnows to 45-foot whale sharks. There are thought to be more than 20,000 species of fish.The Pacific Coast is home to over 900 species from the Gulf of Alaska to Baja California. There are three main groupsof fish – bony fish of class Osteichthyes (for example perch and carp), cartilaginous fish of class Chondrichthyes(including sharks, skates, and rays) and jawless fish of superclass Agnatha (lampreys and hagfish). All fish aremembers of Phylum Chordata, Subphylum Vertebrata.A school is defined as a group of fish mutually attracted to one another and usually includes fish of about the samesize. Schooling is a common social behavior pattern among fish; 25% of all fishes school throughout their lives andhalf of all fishes spend at least part of their lives in schools. Schooling behavior increases in situations where they arevulnerable to capture in large numbers. It is believed that fish use touch or lateral line receptors (for sound and watermovement) and visual cues to maintain their position in a school. Biology 1BAquarium of the Bay Field Trip – 20 Questions by Dr. McCray3At the Aquarium of the Bay you will see at least two displays featuring schooling fish. One of them is the centralcylindrical aquarium – the first tank exhibit encountered near the aquarium entrance. Take a look at these schoolingfish on display. Later you will have another opportunity to watch schooling fish as you proceed downstairs to the“Under the Bay” tanks.Here are some interesting facts to consider regarding schooling:Fast-traveling schools assume a wedge shape, while feeding schools assume a circular shape.Fish that move as a single unit are called “polarized” schooling fish. Those that tend to swim in a less compactshape are “non-polarized.”Most schools break up at night.Similar behavioral strategies are found among terrestrial animals known to form “herds.”Here are some possible advantages proposed for schooling behaviors:Hydrodynamic efficiency. Fish may gain some advantage from the vortices of other fish. Fish produce a slimecoat to protect their skin. Accumulated slime in the water between members of the school may also help to reducedrag. (Drag = slowing due to friction or turbulence.)Reduced risk of predation. This may be particularly so if the group engages in complicated evasive maneuverswhile swimming in a school.Increased efficiency of food finding.Increased reproductive success. It is much easier to find a mate if you’re already in a large social group!Predators that attack schooling fish are known to employ some of these strategies:Attack at low light levelsSwim along with the school and grab fish that make swimming errors, get separated from the school or aresick/injured.Fish predators swimming in schools have better success in catching schooling fish for the same reasons a school ofplankton-eating fish have better success catching plankton. It is not uncommon for a school of predators to drivethe school of prey to the surface, where the prey are also vulnerable to seabirds from above.Activity/Question 3: Write the common name (or, if not available, write a description) of two fish at thisaquarium engaging in schooling behavior. (Write this into your laboratory notebook.)Activity/Question 4: Many schooling fish tend to be silvery. What may be an advantage to this?Activity/Question 5: Describe the shape of the school formed by this species. Does the school swim in aconsistent way or does it seem to change often in its configuration and direction? (Write this into your laboratorynotebook.) Biology 1BAquarium of the Bay Field Trip – 20 Questions by Dr. McCray4Morphological Adaptations of Fish: BODYThe displays for this topic are located in various tanks on both floors of the Aquarium of the Bay.There is great diversity of fish habitats and a great diversity of evolutionary adaptations that allow fish to thrive inthese habitats. Yet all fish are still visibly identifiable as fish. Before you proceed to the tanks be sure you haveacquainted yourself with terms that describe the morphology of fish. The following pages will require you to makedetailed observations of morphological and behavioral adaptations of fish for feeding, defense, and reproduction.Figure 1. Two types of fish bodies: mid-water fast swimmer (left) and bottom dweller (right).Flatfish (shown in Figure 1, right) are born upright like most fish. As larvae they swim upright and their eyes arelocated on either side of the head. During development, one side of the body becomes the top while the other sidebecomes the bottom, and one of the eyes migrates from one side of the head to the other so that both eyes are on thetop. Typically the “eye side” will be cryptically colored (camouflaged) while the belly side is pale. The mouth maydevelop a twist in some species, perhaps to make feeding easier. Many of the over 500 species of flatfish areimportant to commercial fisheries. Flatfish families are organized by; 1) which side of the body their eyes are found(left or right), and 2) whether or not they have large teeth. Species of flatfish vary greatly in size. For example, whilemany species are smaller than the size of your palm, the largest Halibut can weigh over 600 pounds.Activity/Question 6: Write down the name (or, if not available, describe in your own words the appearance)of two species of flatfish seen at the Aquarium of the Bay. Note where in the tank you found it, and on what sideof its body the eyes are located (right or left). Write your answers into your laboratory notebook. Biology 1BAquarium of the Bay Field Trip – 20 Questions by Dr. McCrayFigure 2. Body forms in fishes: a) elongate, fusiform or basslike; b)anguilliform, eellike; c) ovate or truncated; d) compressiform, thin, narrow,deep or perchlike; e) depressiform or flattened; and f) hemispherical orglobiform.Figure 3. Various shapes of the caudal fins of bony fishes. Caudal fins are the“engines” of the fish: a) indented; b) rounded; c) double truncate; d) square;e) forked; f) pointed with fin present; g) pointed with fin not differentiated;and h) naked, without rays on tip.5 Biology 1BAquarium of the Bay Field Trip – 20 Questions by Dr. McCray6Figures 2 and 3 in this handout provide illustrations for terms used to describe body and fin shapes. Those terms arerepeated in tabular form here but you should make sure to consult those illustrations to reacquaint yourself with theshapes and structures so you can answer the questions that follow.Terms to Describe Body ShapeFin TermsTerms to Describe Fin ShapeFusiformPectoral finIndentedAnquilliform or AttenuatedPelvic finRoundedOvate or Truncated(thoracic or abdominal)Double truncateCompressed or CompressiformAnal finSquare, truncate or straightDepressed or DepressiformAdipose finForkedGlobiform or HemisphericalCaudal or tail finPointed with fin presentFinletsPointed with fin not differentiatedDorsal finNaked, without rays on tipBody Shape (Figure 2) allows you to predict the fish’s likely swimming style. Some fish swim at high speeds becausethey either need to catch food, avoid predators, or to maintain their position in strong currents. Fast fish havestreamlined bodies resembling a torpedo shape, and tails that have a very narrow area to the base of the tail tominimize drag (Figure 3). Fish that don’t need a burst of speed have evolved less streamlined bodies. The body of aslower fish is typically deeper and flatter, ideal for maneuvering between plants. Fish with fatter and more roundedbodies are more stable in fast flowing water.Very fast swimming fish additionally have special fin adaptations including finlets and keels. Finlets (Figure 1, left)are little median fins dorsally and ventrally that help to reduce drag. A keel is a lateral protuberance on the caudal endthat offers stability while swimming at great speeds. Since this is an aquarium that only specializes in fish found in theSan Francisco Bay, there are probably no fish here with finlets and/or a keel. Those are mostly found in pelagic (openocean) species such as tuna.Figure 4. Terminology of various mouth and snout forms: a) lower jawprojecting beyond the upper jaw, a surface feeder; b) a tubular jaw withjaws at the tip; c) inferior, bottom-feeding mouth; d) swordlike beak; e)terminal; and f) extended upper jaw with lower lip inferior.Activity/Question 7. Write the name or, if not available, describe a fish that swims very quickly. Use theterminology above to describe its morphology. Do the same for a slow-moving fish. Write all your observationsinto your notebook. Biology 1BAquarium of the Bay Field Trip – 20 Questions by Dr. McCray7Morphological Adaptations of Fish: MOUTH/JAW SHAPE & POSITIONMouth shape and position (Figure 4) can tell you a great deal about the type of prey items a fish will likely eat as wellas its mode of food capture.Terminal: directly on the front of the body. This is typical of mid-water dwellers.Inferior: overhanging – mouth opens ventrally. This is typical of bottom dwellers who eat foods on the benthos(substrate).Superior mouth: projecting lower jaw – mouth opens dorsally. This type of mouth suits fish who feed on items foundnear the surface.Tubular snout with jaws at the tip – consistent with “picker” style of feeding (like many reef fishes).Barbels and “whiskers” are specialized fleshy structures near the mouth that assists in sensing prey items in thebenthos.Activity/Question 8:Copy the table headings below into your laboratory notebook, leaving ample space for drawings and notes of yourobservations. You must locate 4 examples of the 8 fishes listed below and determine their body shape, mode ofswimming (propulsion fins), and mouth shape. Use those observed characteristics to make predictions about the habitatand prey of the fish (small vs. large) in nature. Some information may be available on interpretive signs near thedisplay tanks. You can do more than 4 if you wish, and if time permits.Table headings to include in your notebook. Leave plenty of space for your notes:Name of FishBody ShapePropulsion Fin(s) –Mouth Shapedorsal vs. caudalfinPipefishWrasseSome tropical fish (top floorhexagonal tank) of your choiceLeopard sharkCabezon or RockfishBat rayHalibut, Sole or Flounder (notalways visible)Anchovy or sardine (whatever isavailable)Predicted habitatand prey typeFish Communication Using Colors and PatternsThe displays for this topic are located in various tanks on both floors of the Aquarium of the Bay.The colorful fish found in the hexagonal tropical tank (top floor of the aquarium, not far from the entrance) are notfound in – or anywhere near – San Francisco Bay, but they provide contrast to illustrate how the species of the clear,warm tropics rely on bright coloration and symbiotic relationships for protection from predators, whereas the speciesof the murkier, colder waters of the Bay Area have evolved to use camouflage to avoid predation.Fish communication involves visual signals of color, pattern and subtle movements of the body and fins.Balance must be struck between the need to be visible for intraspecies communication (intraspecies means “amongmembers of the same species”) and the need to avoid detection by predators. Some noteworthy trends of fishcoloration and patterns follow:Poster Colors. View the fishes occupying the hexagonal tropical tank, paying special attention to the bright colorsand dramatic patterns. These colorations are generally thought of as some kind of “territory advertisement.” But thereare other possible functions also. They may play roles in sex and courtship as signs of sex, status and maturity. Manyspecies with “poster colors” engage in a predator avoidance strategy called the “flash effect.” Predators can become Biology 1BAquarium of the Bay Field Trip – 20 Questions by Dr. McCray8confused if a poster colored fish first displays its broad side, but then as the fish suddenly turns its body to display itsmore narrow profile it seems to “disappear” from the predator’s view. At least in a few of the fish known for theirposter colors they may just as easily be called examples of aposematic coloration. Aposematic coloration gives avisual equivalent of telling predators “I am poisonous!” or “I’m too spiny for you to eat!”Red Coloration. When viewing the fish native to the San Francisco Bay, you may notice some that display redcoloration. Red wavelengths are the first to get screened out as light enters the water. Red fish tend to be nocturnal orlive at depths where red light is pretty much absent from the water. This means that in their natural light levels (depthor darkness) they are cryptic and blend in with their surroundings. For certain tidepool-dwelling fishes their red colorhelps them blend in with surrounding red algae. In other locales, shallow-water freshwater fishes tend to limit the useof conspicuous red markings to mating activities. In these cases the red stands out well when viewed from shortdistances but the red markings become more difficult to see the further away the beholder is. It is commonly thoughtthat the short-distance viewing of red is great for displaying to potential mates while offering decent hiding frompredators further away.Activity/Question 9: Name (if available) and sketch a fish exhibiting red coloration. If the information isavailable, describe the natural habitat of this species. (Write this into your laboratory notebook.)Activity/Question 10: Name (if available) and sketch a fish exhibiting poster colors. If the information isavailable, describe the natural habitat of this species. (Write this into your laboratory notebook.)Disruptive coloration. Colors and patterns disrupt the outline of fish to make them less visible. Many of these fishesare found associated with aquatic plants. Vertical bars on the bodies of these fish probably help them blend in with thevertical orientation of plants.Activity/Question 11: Name (if available) and sketch a fish exhibiting disruptive coloration. If theinformation is available, describe the natural habitat of this species. (Write this into your laboratory notebook.)Camouflage. Slow-moving bottom fishes are able to match their backgrounds very well. Flounders, sole and halibutare famous for this ability. In laboratory settings some of these fish can even do a decent job of matching the pattern ofa checkerboard.Activity/Question 12: Look again at your drawings/descriptions of the flatfish. What anatomical adaptationdo you see in this fish that would give it an advantage in blending into its environment?Countershading. Most fish display this. Being dark dorsally helps them avoid visual detection by predators attackingfrom above, while being light ventrally helps them similarly avoid detection by those attacking from below.Activity/Question 13. Look for countershading in specimens of the “Under the Bay” overhead tank display.Name (if available) and sketch into your lab notebook one example of a fish that exhibits countershading.Eye ornamentation. Fish can either disguise their eyes or make them more conspicuous. Eyes are a focus-point forpredators and are important in visual communication among individuals of the same species. There are two strategiesfor eye ornamentation in fish:Disguise the eyes. This is most common. Fish display pigmented lines that appear to cross the eye region.These lines tend to run vertical on deep-bodied species but horizontal on slender-bodied species.Emphasize the eyes. This is perhaps most obvious in reef fish that have lots of small crevices to hide in casethey are noticed by predators. Eyes are made more obvious through bright colors and in some cases eye rings. Biology 1BAquarium of the Bay Field Trip – 20 Questions by Dr. McCray9Activity/Question 14: Name (if available) and sketch a fish that features eye ornamentation to disguise theeyes. If such a fish is available, name and sketch one fish that features eye ornamentation that emphasizes orexaggerates the eyes. (Write this into your laboratory notebook.)Eye spots. A large number of fish display dark spots that resemble eyes in shape and are surrounded by lighterpigmentation to help these spots stand out. In many cases these “false eyes” are positioned at the base of the tail,presumably to trick potential predators. These spots may also help in intraspecies communication also, such as duringschooling or courtship.Activity/Question 15: Name (if available) and sketch a fish that features eye spots or “false eyes.” Hint: youmay find a good example from class Chondrichthyes somewhere in this aquarium. (Write this into your laboratorynotebook.)Lateral stripes. Usually a single, midlateral band seen in schooling fishes. May help school members maintain theirposition and confuse predators by making it harder to visually pick one out of the crowd.Activity/Question 16: Name (if available) and sketch a fish that features lateral stripes. (Write this into yourlaboratory notebook.)Polychromatism. Different populations may feature certain color “morphs” such as gold vs. plain, bright vs. dull.Brightly colored morphs may be preferred by potential mates, may be more aggressive in feeding, but may also bemore vulnerable to predators.Special patterns. Some spots or patterns play a specific role in reproduction, as in certain cichlid fish. Cleaner fisheson reefs tend to have special coloration to advertise their services. Some fish mimic the coloration of other fishes orinvertebrates.Photophores. These are spots that produce light. They feature most prominently in mid- or deep-depth ocean dwellers.Photophores may play roles in intraspecific communication and at least in some cases may help confuse predatorslooking at them from below in the darkness.IV. UNIQUE ADAPTATIONS OF CHONDRICHTHYESThe…
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