1. Lesson 19: Vertebrates I Marine Biology

2.  Animals in the sub-phylum Vertebrata have spinal cords and brains  Marine vertebrates include: sharks, fish, turtles, birds, seals and whales  Can you think of others? 2 VERTEBRATES: ANIMALS WITH A BACKBONE Classification Overview Common Vertebrates Phylum Subphylum Chordata Vertebrata Classes Chondrichthyes Actinopterygii Reptilia Mammalia

3. FISHES  Aquatic vertebrates that are characterized by:  Paired fins  Used for movement  Scales  Used for protection  Gills  Used for exchanging gases

4. EVOLUTION OF FISHES  Fishes were the first vertebrates to evolve  The evolution of jaws and the evolution of paired fins were important developments during the rise of fishes

5. THE FIRST FISHES  Jawless creatures whose bodies where armored with bony plates  Lived in the oceans during the late Cambrian Period, about 510 mya  Fishes kept this armored, jawless body plan for 100 million years

6. THE AGE OF FISHES  Ordovician and Silurian Periods: 505-410 mya, fishes underwent a major adaptive radiation  Devonian Period: “Age of Fishes”  Some were jawless with little armor  Ancestors of modern hagfishes and lampreys  Others were armored & ultimately became extinct about 360 mya

7. THE ARRIVAL OF JAWS  Other ancient fishes kept their bony armor and possessed a feeding adaptation that would revolutionize vertebrate evolution: JAWS  Jawless fishes  Limited to eating small particles of food that they filter out of the water or suck up like a vacuum cleaner  Jaws can hold teeth and muscles  Much wider variety of food  Defend themselves by biting

8. THE ARRIVAL OF PAIRED FINS  More control of body movement  Fin tails and powerful muscles gave greater thrust when swimming  Enabled fishes to move in new and varied patterns  This enabled fishes to use their jaws in complex ways

9. THE RISE OF MODERN FISHES  Although the early jawed fishes soon disappeared, they left behind two major groups that continued to evolve and still survive today  Ancestors of modern sharks and rays: skeletons made of resilient cartilage  Group that evolved skeletons made of true bone

10. FORM AND FUNCTION IN FISHES  Adaptations to aquatic life include:  Various modes of feeding  Specialized structures for gas exchange  Paired fins for locomotion

11. FEEDING  Herbivores, carnivores, parasites, filter feeders, detritus feeders  A single fish may exhibit several modes of feeding (carp: eat what is available) while others are very specialized (barracuda: carnivore)  Pyloric ceca: finger-like pouches found in many species of fish that secrete digestive enzymes to help digest food

12. RESPIRATION  Gills  located on either side of the pharynx  made up of feathery filaments  Lampreys and sharks have several gill openings on the side of the body  A number of fishes, such as the lungfish, have an adaptation that allows them to survive in oxygen-poor water or in areas where bodies of water often dry up

13. RESPIRATION

14. EXCRETION  Most fishes rid themselves of nitrogenous wastes in the form of ammonia  Gills, kidneys  Saltwater fishes  Lose water by osmosis: kidneys return as much water to the body as possible  Freshwater fishes  Gain water by osmosis: kidneys pump out plenty of dilute urine

15. RESPONSE  Lateral line system: sensitive receptor system that enables fish to detect gentle currents and vibrations in the water (the 6 th sense)

16. MOVEMENT  Most move by alternately contracting paired sets of muscles on either side of the backbone  Because their body tissues are more dense than the water they swim in, sinking is an issue for fishes  Swim bladder: gas-filled organ found in many bony fishes that adjusts their buoyancy

17. REPRODUCTION  Oviparous: term used to refer to animals whose eggs hatch outside the mother’s body  Ovoviviparous: term used to refer to animals whose young are born alive after developing in eggs inside the mother’s body  Viviparous: term used to refer to animals that bear live young that are nourished directly by the mother’s body as they develop

18. ECOLOGY OF FISHES  Anadromous: fishes that spend most of their lives in the ocean but migrate to fresh water to breed  Examples: lampreys, sturgeons, and salmon  Catadromous: fishes that spend most of their lives in fresh water but migrate to the ocean to breed  Example: European eel, American eel

19. GROUPS OF FISHES  Over 24,000 living species that are extremely diverse  Jawless fishes  Cartilaginous fishes  Bony fishes

20.  Superclass Agnatha: Simple, more primitive fish that lack jaws  Characteristics include:  No jaws  Cartilaginous skeletons  Lack scales, paired fins  Long, eel-like  Two class divisions:  Myxini (hagfish)  Petromyzontida (lampreys) 20 AGNATHA: THE JAWLESS FISHES

21. 21 SOME AGNATHANS Pacific hagfish off Oregon Coast Sea Lamprey Fish with 2 sea lampreys attached

22.  Class Chondrichthyes means ‘cartilaginous fish’ and consists of sharks, rays, skates and close relatives  They share common features:  Jaws  Cartilage skeletons, not true bone  Fatty liver used for buoyancy  Lack swim bladder  Most have placoid scales  They are great predators because they have pore-like structures near their snouts called ampullae of Lorenzini, which detect electrical currents of other organisms 22 CHONDRICHTHYES: CARTILAGINOUS FISHES

23. 23 SOME CHONDRICHTHYES Basking shark 2 nd largest fish in the sea behind the whale shark. It feeds on plankton Order: Lamniformes Stingray They ‘fly’ through the water using flat, modified fins Order: Rajiformes

24.  Superclass Osteichthyes contains the majority of the ocean’s fish  Characteristics include:  Bone skeletons  Operculum: bony skin flap outside gills that helps fish breathe when not swimming  Most use a swim bladder to keep them from sinking 24 OSTEICHTHYES: THE BONY FISHES

25. BONY FISHES: TRUE BONE SKELETONS  Class Osteichthyes  Ray-Finned Fishes (Actinopterygii)  Skeletons made of true bone  Examples: eels, goldfish, and catfish  Lobe-Finned Fishes (Sarcopterygii)  Fleshy fins  Ancestors of tetrapods (4-limbed vertebrates)  Few modern examples: lungfishes and coelacanths

26. 26 SOME OSTEICHTHYES Yellowfin tuna Ray-finned fish Indonesian coelacanth Lobe-finned fish Walleye pollock Ray-finned fish

27.  http://ed.ted.com/lessons/the-coelacanth-a-living-fossil-of-a- fish-erin-eastwood http://ed.ted.com/lessons/the-coelacanth-a-living-fossil-of-a- fish-erin-eastwood THE COELACANTH: A LIVING FOSSIL OF A FISH 27

28. Fish use their fins to help them swim How big is that fish? GyotakuGyotaku 28 ANATOMY OF A BONY, RAY-FINNED FISH adipose fin

29. GYOTAKU 29

30.  Perch dissection  Shark notes  Shark dichotomous key  Shark worksheets  Shark project  … A Break from notes… 30

31.  Fishing contributes significantly to the U.S. economy and provides a vital food source.  Think back to the exercise at the beginning of class: how did you estimate the number of fish in your container?  Scientists use a combination of math, biology, and computer skills to best determine what levels of fishing can exist to provide food and support the economy without overfishing the resource.  NOAA’s National Marine Fisheries Service works to sustainably manage our marine resources, including commercial fish populations, and to promote healthy ecosystems. 31 MANAGING FISH POPULATIONS

32.  A fish stock is group of individuals of the same species that inhabit the same geographic region and interbreed when mature  Single species may be made up of multiple stocks (each in a different geographic region), and fisheries are managed at the stock level.  An example of a stock is a group of salmon that always use and return to particular stream for reproduction.  Biomass (B) is the total weight of fish in a stock (e.g., metric tons)  Fishing mortality rate (F) is the rate at which fishing removes fish from a stock 32 FISHERIES MANAGEMENT TERMINOLOGY

33.  Sustainability represents the ability to persist in the long term  If a fish stock remains at a constant level (or even grows) despite fishing pressure over a long time period, it is considered sustainable  Maximum sustainable yield (MSY) is the greatest number of fish that can be caught each year without impacting the long-term productivity of the stock  Overfishing occurs when fishing mortality exceeds a specific threshold, usually set at a level to achieve MSY  A stock is considered overfished when the stock size falls below a specific threshold, either in terms of numbers or biomass 33 FISHERIES MANAGEMENT TERMINOLOGY

34.  In today’s activity, we will discuss in more detail what it means to fish “sustainably” and you will evaluate sustainable seafood restaurants. 34 STUDENT ACTIVITY

35.  Reptilians generally share these common features:  Ectothermic (cold-blooded): they take on the temperature of their surroundings***  Breathe with lungs  Reproduce by laying eggs CLASS REPTILIA: EXOTHERMIC ANIMALS* Classification Overview Common Reptilian Orders Sub-PhlyumClass Vertebrata Reptilia Orders Crocodilia – Alligators Crocodiles Chelonia – Turtles, Tortoises Squamata – Snakes, Lizards

36. REPTILES  Evolved from ancient amphibians  First vertebrates to evolve adaptations to drier conditions  Dry, scaly skin, well-developed lungs, strong limbs, shelled eggs BIRDS (endothermic)  Examples: lizards and snakes, crocodilians, turtles and tortoises, tuatara…and BIRDS (endothermic)!

37. 37 SOME MARINE REPTILES Marine iguana – Order Squamata These reptiles eat algae in cold water near the Galapagos Islands They warm themselves on rocks after their dives Green sea turtle – Order Testudines Sea turtles crawl onto the beach to lay their eggs When eggs hatch, babies must crawl to sea – on the way they are highly vulnerable to seabirds and other predators

38.  http://ed.ted.com/lessons/the-survival-of-the-sea-turtle http://ed.ted.com/lessons/the-survival-of-the-sea-turtle  Tour de Turtles: It’s a Race for Survival!  Turtle dichotomous key  Turtle “board game” THE SURVIVAL OF THE SEA TURTLE

40. SEA TURTLE LIFE CYCLE

41. WHAT THREATS TO SEA TURTLES FACE? Within your group your goal is to:  Use the Tour de Turtles website to research your assigned threat to sea turtle survival.  http://www.tourdeturtles.org/causes.php http://www.tourdeturtles.org/causes.php  Prepare a 1-2 minute presentation to share what you have learned.

42. TRACK YOUR TURTLE! Check the Tour de Turtles website to see how your turtle is competing:  http://www.tourdeturtles.org/ http://www.tourdeturtles.org/  Who will complete the marathon first?  Which turtle will raise more money for her cause through adoptions?

43. Lesson 20: Vertebrates II Marine Biology

44. Classification Overview Common Vertebrates Phlyum Subphylum Chordata Vertebrata Classes Chondrichthyes Actinopterygii Reptilia Mammalia VERTEBRATES: ANIMALS WITH A BACKBONE 44  We’ve been learning about marine life in the sub-phylum vertebrata  What are some common features of this sub-phylum?  Today we’ll conclude our survey of life in the sea by taking a look at the class mammalia

45. ENDOTHERMIC ANIMALS 45  Marine mammals are endothermic (warm-blooded): they keep a constant internal temperature  They also share other characteristics:  Hair on some part of the body  Mammary glands to provide milk to young Classification Overview Common Mammalian Orders Sub-PhlyumClass Vertebrata Mammalia Orders Pinnipedia – Seals, Sea Lions, Walrus Cetacea – Dolphins, Whales Sirenia – Manatees, Dugong

46.  Heat loss in the water is faster than in the air, even at the same temperature  So how do marine mammals maintain their body temperatures?  Countercurrent heat exchange - Insulation (blubber, fur) - Behavioral strategies (coming to the surface to get warm) - High metabolism 46 HEAT LOSS IS HIGH IN THE OCEAN Heat from blood traveling through the arteries is transferred to blood traveling back to the body core from the extremities, so that heat isn’t lost to the environment

47.  Order Pinnipedia refers to mammals with large fin-like flippers including sea lions, seals and walruses  Pinnipeds come onto the shore to breed and, like other mammals, give birth to live young  Do you know the difference between a seal and a sea lion? 47 Pinnipeds: Animals with “fin feet”

48. SEALS AND SEA LIONS  Seals lack ear flaps and have rear flippers that point backward  Because they can’t rotate their flippers, they don’t move very well out of water  Sea lions have ear flaps  Sea lions can rotate their flippers forward and thus are more mobile out of water Steller Sea Lion Spotted Seal ear flap

49.  Cetaceans are highly adapted to life underwater  They share several characteristics  No hind limbs  Muscular tail  Fish-like body form  Blowhole at the top of the head for breathing  Blubber (fat layers) to insulate the body 49 ORDER CETACEA: WHALES, DOLPHINS, AND PORPOISES

50.  Did you know that some whales don’t have teeth?  Baleen whales trap food in their mouths using a broom-like filter that catches krill and small fish  Many of the largest whales belong to this sub-order 50 BALEEN WHALES: SUBORDER MYSTICETI

51. BALEEN Baleen whales all possess hundreds of plates of baleen instead of teeth. Baleen is made of keratin and hangs from the upper jaw. The fringed baleen plates trap engulfed prey and filter out water. Throat of some baleen whales (Rorqual) is pleated like an accordion to expand and hold the large amounts of water

52. Humpback whales are known for their complex songs Males use these songs to communicate and to court females Blue whales, shown above, can be up to 90ft long http://youtu.be/o5MPbZZ4xJAhttp://youtu.be/o5MPbZZ4xJA Why Are Blue Whales So Enormous? They are identified by their characteristic skin pigmentation 52 Let’s meet some baleen whales

53.  Unlike the baleen whales, marine mammals in the suborder Odontoceti have teeth  This suborder includes dolphins, orcas (killer whales) and the sperm whale  These mammals use sound waves (echolocation) to help find their way underwater, to communicate and in some cases to hunt prey 53 TOOTHED WHALES: SUBORDER ODONTOCETI

54. 54 Let’s meet some toothed whales The sperm whale primarily hunts deep ocean squid, including the giant squid, which can grow over 50 feet long Pacific white-sided dolphins (below) are very social mammals, usually traveling in groups of 10-100 dolphins http://video.nationalgeographic.com/video/animals/mam mals-animals/whales/weirdest-narwhals/

55. Dolphins and porpoises are both toothed whales, but they are in separate families 55 DOLPHINS AND PORPOISES Dolphins (Delphinidae)Porpoises (Phocoenidae) Teeth are cone-shapedTeeth are flattened Beak-shaped snoutBlunt snout Hooked or curved dorsal finSmall, triangular dorsal fin Often seen at surfaceSeen only briefly at surface

56. SIZE COMPARISON

57. In today’s activity, you will practice identifying marine mammals. 57 STUDENT ACTIVITY