Ch. 1 -3 Citizens of the Sea

What unique feature do Barreleye fish possess?

They have tubular eyes that can rotate upwards to spot prey and have a transparent dome over their eyes for protection.

How do the eyes of many bony fish differ from those of cartilaginous fish?

Many bony fish can see color, while cartilaginous fish typically cannot.

What is unique about the vision of stomatopods (mantis shrimp)?

They have 16 visual pigments and can see UV, polarized, and infra-red light, as well as stereo vision with one eye.

Which aquatic organisms have eyes that can focus and resemble human eyes?

Box jellyfish have human-like eyes that can detect light and focus.

What is olfaction in aquatic organisms?

Olfaction is the sense of smell, well-developed in many aquatic organisms, used to detect food, mates, and predators.

What are olfactory sacs?

Olfactory sacs contain special sensory cells and are connected to the outside by nares.

What is gustation?

Gustation is the sense of taste, with taste buds located in mouths or on barbels in some fish.

What is the function of the lateral line in fish?

The lateral line detects vibrations and helps fish sense prey, predators, and maintain schooling.

What are the ampullae of Lorenzini?

They are sensory organs in cartilaginous fish that detect weak electric fields of other organisms.

How does sound travel in water compared to air?

Sound travels four times as far in water than in air.

What role does sound play in marine organisms?

Sound is used for threat displays, species identification, mating rituals, and communication.

What is echolocation?

Echolocation is a natural sonar used by some marine mammals to produce sound waves that reflect back to determine the size and shape of objects.

What is the function of the melon in toothed whales?

The melon is a fatty structure that helps focus outgoing sound waves during echolocation.

What is magnetoreception?

Magnetoreception is the ability of some species to detect Earth's magnetic field for orientation and navigation.

Which species are known to use magnetoreception?

Sharks, sea turtles, and salmon are known to use Earth's magnetic field for navigation.

What is mechanoreception in aquatic organisms?

Mechanoreception is the sense of touch, exemplified by the vibrissae of walruses that detect prey buried in sediment.

How do marine mammals communicate besides vocalizations?

Marine mammals also communicate through postures and movements, such as tail slaps.

What was the Census of Marine Life?

A decade-long worldwide study involving thousands of scientists to survey marine life, determine species diversity, and document changes in species numbers and abundance.

Who is known as the Father of Modern Taxonomy?

Carl von Linne (Linnaeus), who created binomial nomenclature for species naming.

What is DNA barcoding?

A technique to identify species by sequencing short fragments of certain genes and comparing them to known taxonomy.

Which three domains of life are represented in the marine environment?

Bacteria, Archaea, and Eukarya.

What are marine microbes?

The most abundant life forms in the ocean, including viruses, prokaryotic bacteria, archaea, and single-cell eukaryotes, which significantly affect marine ecosystems.

What are the major divisions of phytoplankton?

Prokaryotic (Cyanobacteria) and Eukaryotic (Haptophyta, Ochrophyta, Bacillariophyta, Dinophyta).

How are marine viruses characterized?

Marine viruses are typically not considered living organisms and are ten times more abundant than marine prokaryotes.

What is the role of marine prokaryotes?

They are the simplest and oldest forms of life, acting as primary producers and decomposers in marine ecosystems.

What defines algae?

A diverse group of simple eukaryotic aquatic organisms that contain chloroplasts and are considered protists.

What are seagrasses?

The only true marine angiosperms that can be fully submerged by salt water.

What are the major categories of marine invertebrates?

Sponges, Cnidarians, Comb jellies, Flatworms, Nematodes, Segmented worms, Mollusks, Arthropods, and Echinoderms.

What distinguishes Cnidarians?

They are multicellular organisms with specialized tissues that allow for complex behaviors, including jellyfish and corals.

What are the three major categories of fishes?

Agnatha (jawless), Chondrichthyes (cartilaginous), and Osteichthyes (bony).

What are the characteristics of marine reptiles?

They are descended from land reptiles, are ectothermic, air-breathing, and covered with dry scales.

How many species of sea turtles are recognized?

Seven commonly recognized species, including Green, Hawksbill, Leatherback, Flatback, Loggerhead, Kemp's Ridley, and Olive Ridley.

What adaptations do sea snakes have?

They are laterally flattened, use paddle-shaped tails for swimming, and can absorb some oxygen through their skin.

What are the defining traits of marine mammals?

They are endothermic, homeothermic vertebrates that are viviparous and produce milk for their young.

What are pinnipeds?

Marine mammals with flippers for swimming, including seals and sea lions, that return to land to rest and breed.

What is unique about sea otters?

They are the smallest marine mammals and lack blubber, relying on dense fur for insulation.

What do sea cows eat?

They are strict vegetarians, primarily feeding on seagrasses.

What are the two groups of cetaceans?

Toothless (baleen) whales and toothed whales.

What is the role of baleen in mysticeti whales?

Baleen plates made of keratin strain plankton and small fish from the water.

What distinguishes odontoceti whales?

They have teeth to catch prey items such as fish and squid.

What is the largest toothed whale?

The sperm whale, known for its deep diving capabilities.

What is countershading in marine species?

A form of camouflage with a dark ventral surface and lighter bellies, helping to blend in with the water column.

How do open water fish typically appear?

They are rarely colorful and often have silvery sides that blend into the open water environment.

What is the purpose of transparency in marine organisms?

To 'disappear' in the open water column, common in larval stages and some invertebrates.

What does cryptic coloration refer to?

Body color, texture, and shape that blend into the environment to hide from predators or ambush prey.

Give an example of a fish that uses cryptic coloration.

The predatory scorpionfish, which resembles sponges and rocks around coral reefs.

What is aposematic coloration?

Warning coloration of bright colors or patterns displayed by poisonous or toxic species.

What is Mullerian mimicry?

Different toxic species display similar color patterns to reinforce a warning message.

What is Batesian mimicry?

A non-toxic species mimics the color patterns of a toxic species to gain protection from predators.

What is aggressive mimicry?

A predatory strategy where a species mimics a harmless or attractive item to lure prey.

How do anglerfish use aggressive mimicry?

They dangle a small knob of flesh to mimic prey items, attracting fish that are then eaten.

What is disruptive coloration?

Strong visual patterns that break up the silhouette of fish, making them less obvious to predators.

What is the function of false eyespots in some marine animals?

To draw a predator's attention away from vital body parts and confuse them about the prey's direction.

How do cephalopods like squid and octopus use ink?

To hide from or confuse predators, produced from an internal ink sac.

What is dynamic camouflage?

The ability of some species, like mimic octopus and flounder, to adjust their appearance to match their environment or mimic other species.

What are chromatophores?

Pigment-filled sacs in the skin of some animals that change color under neural and muscular control.

What role does mimicry play in predator-prey interactions?

It can provide protection for prey species or enhance predation success for mimic species.

What is the significance of color patterns in nudibranchs?

They are highly colored and patterned to warn predators of their toxicity, which they acquire from their diet.

What is the purpose of a cleaner wrasse in marine ecosystems?

They perform symbiotic duties by cleaning parasites from larger fish.

How does the saber-toothed blenny exploit mimicry?

By mimicking cleaner wrasses to get close to larger fish and take bites instead of cleaning them.