Vertebrates and Their Classification

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Questions and Answers

What is the primary behavior of hammerhead sharks during the day?

Resting near the ocean floor

Mating

Schooling (correct)

Hunting for prey

How do whale sharks primarily feed?

By scavenging from the ocean floor

By ambushing prey

As filter-feeders (correct)

By hunting fast-moving fish

What is the reproductive method of most sharks, including whale sharks?

Oviparous

Ovoviviparous (correct)

External fertilization

Viviparous

What structure nourishes the growing embryo in shark egg cases?

Yolk Signup and view all the answers

What adaptation helps the stingray blend into its environment?

Camouflage against the sandy bottom Signup and view all the answers

What type of marine animal is the spotted ratfish?

A cartilaginous fish Signup and view all the answers

Which of the following best describes the typical environment of hammerhead sharks?

Open ocean Signup and view all the answers

What aspect of shark embryos can typically be observed in their egg cases?

Transparency through the egg cases Signup and view all the answers

What is a defining characteristic of the subphylum Craniata?

Presence of a cranium Signup and view all the answers

What distinguishes vertebrates from other animal groups?

Presence of a backbone Signup and view all the answers

Which of the following is a characteristic feature of Dunkleosteus?

Armored head and neck with bony plates Signup and view all the answers

What feeding strategy do sea lampreys use to feed on their host fish?

Rasping flesh using rough tongues Signup and view all the answers

During which period did Dunkleosteus exist?

Devonian Signup and view all the answers

What is a primary habitat for Pacific hagfish?

Ocean floor Signup and view all the answers

What type of skeleton do craniates possess?

Bony and cartilaginous Signup and view all the answers

What common misconception may arise about the teeth of Dunkleosteus?

It possessed true, traditional teeth Signup and view all the answers

What distinguishes anapsids from synapsids and diapsids?

Anapsids have no openings in their skulls. Signup and view all the answers

How many temporal fenestrae do synapsids possess?

One opening. Signup and view all the answers

Which statement about pterosaurs is correct?

Pterosaurs were believed to have soared after launching from cliffs. Signup and view all the answers

What era is associated with the existence of Edmontonia?

Late Cretaceous period. Signup and view all the answers

What is currently debated regarding Testudines?

Their evolutionary placement. Signup and view all the answers

Which of the following dinosaurs is noted for its armoring?

Edmontonia. Signup and view all the answers

In the evolution of amniotes, what is a characteristic of diapsids?

They have two temporal fenestrae. Signup and view all the answers

What type of dinosaurs were Herrerasaurus and Eoraptor?

Saurischian dinosaurs from the Triassic. Signup and view all the answers

What is the primary function of hollow, pneumatic bones in birds?

To reduce body weight for easier flight Signup and view all the answers

How does avian respiration differ from mammalian respiration?

Air flows unidirectionally in birds Signup and view all the answers

During avian respiration, what happens during the first exhalation?

Air moves from posterior air sacs to the lungs Signup and view all the answers

What is the total number of breathing cycles required for a complete ventilation cycle in birds?

Two breathing cycles Signup and view all the answers

Where does air go after the second inhalation in avian respiration?

It moves into the lungs Signup and view all the answers

What anatomical structure do birds primarily use for gas exchange?

Lungs Signup and view all the answers

What is the function of anterior air sacs in birds during respiration?

To expel air from the body Signup and view all the answers

Which of the following pairs correctly matches a bird characteristic with its function?

Pneumatic bones – facilitate efficient flight Signup and view all the answers

What is the approximate length of the tarsier, Carlito syrichta, from nose to the base of the tail?

5 inches Signup and view all the answers

Which of the following statements about howler monkeys is true?

They are known for their loud calls resembling a lion's roar. Signup and view all the answers

Which feature is a characteristic of all great apes?

They share a similar skeletal structure. Signup and view all the answers

What distinguishes the lesser ape, the white-cheeked gibbon, based on gender?

Females and infants are buff while males are black. Signup and view all the answers

What identification is true for the young chimpanzee mentioned in the text?

It is classified as one of the great apes. Signup and view all the answers

What type of relationship does the chart show regarding Hominins?

It shows their evolutionary relationship to modern humans. Signup and view all the answers

Which of the following is true regarding the tail of the tarsier?

It is about twice the length of the body. Signup and view all the answers

What is a unique physiological characteristic of the tarsier?

Its eyes are about the same size as its brain. Signup and view all the answers

What period did cynodonts first appear in?

Late Permian period Signup and view all the answers

What does the presence of holes in the upper jaws of cynodonts suggest?

They had whiskers indicating possible presence of hair. Signup and view all the answers

What characteristic of the morganucodont Megazotrodon suggests its likely behavior?

It may have been nocturnal and insectivorous. Signup and view all the answers

Which of the following statements is true about monotremes like the platypus?

They possess a leathery beak and lay eggs. Signup and view all the answers

What is a defining anatomical feature of a morganucodont's jaw?

A double hinge structure. Signup and view all the answers

Which statement correctly describes the echidna?

It lays eggs and has long hair modified into spines. Signup and view all the answers

Which of these animals is classified as a marsupial?

Tasmanian devil Signup and view all the answers

Which of the following is NOT a characteristic of cynodonts?

They had exclusively aquatic lifestyles. Signup and view all the answers

What is the primary feeding strategy of whale sharks?

Filter-feeding Signup and view all the answers

What reproductive method is exhibited by most sharks, including whale sharks?

Ovoviviparous Signup and view all the answers

Which characteristic allows stingrays to thrive in their environment?

Camouflage with the ocean floor Signup and view all the answers

What feature is common among shark embryos found in their egg cases?

Visibility through transparent structures Signup and view all the answers

What is a notable size characteristic of whale sharks?

Over 10 meters long Signup and view all the answers

During which time of day do hammerhead sharks primarily hunt for prey?

At night Signup and view all the answers

Which of the following animals is specifically adapted to blending in with the ocean floor?

Stingray Signup and view all the answers

What structure in shark egg cases provides nourishment to embryos?

The yolk Signup and view all the answers

What characteristics do adult lancelets retain throughout their life cycle?

All five key characteristics of chordates Signup and view all the answers

What happens to the notochord and nerve cord in the adult stage of tunicates?

They disappear along with the tail Signup and view all the answers

Which of the following structures is NOT retained by adult tunicates?

Notochord Signup and view all the answers

Which feature is present in the larval stage of tunicates but not in their adult form?

Post-anal tail Signup and view all the answers

What is the primary feeding mechanism of colonial tunicates?

Feeding on phytoplankton Signup and view all the answers

What term describes the reproductive strategy of salps?

Sequential hermaphroditism Signup and view all the answers

Which of these features is characteristic of all chordates during some stage of development?

Pharyngeal slits Signup and view all the answers

In which stage do tunicates possess all five characteristics typical of chordates?

Larval stage Signup and view all the answers

What is one characteristic of cynodonts that suggests they may have had hair?

Holes in the upper jaws Signup and view all the answers

Which of the following describes the jaw structure of the morganucodont Megazotrodon?

A double hinge involving two sets of bones Signup and view all the answers

What reproductive method is characteristic of monotremes like the platypus?

Egg-laying Signup and view all the answers

Which feature distinguishes the echidna from other mammals?

Leathery beak and spines Signup and view all the answers

What type of diet is suggested for the morganucodont based on its classification?

Nocturnal and insectivorous Signup and view all the answers

What is one defining feature of marsupials like the Tasmanian devil?

Have a pouch for carrying young Signup and view all the answers

In modern mammals, which bones have the articular and quadrate bones evolved into?

The middle ear bones Signup and view all the answers

Which period is marked by the first appearance of cynodonts?

Late Permian Signup and view all the answers

What is the primary function of air sacs in the respiratory system?

To facilitate gas exchange with the bloodstream Signup and view all the answers

What significant feature did Archaeopteryx possess that indicated its bird-like characteristics?

Flight feathers similar to modern birds Signup and view all the answers

Which ancestors contributed to the structure of the mammalian middle ear bones?

Bones of the jaw and skull in reptiles Signup and view all the answers

What does the presence of claws on the wings of Archaeopteryx suggest?

It retained some characteristics of its dinosaur ancestors Signup and view all the answers

Which of the following statements best describes Shanweiniao cooperorum?

An Enantiornithes species that went extinct after the Cretaceous period Signup and view all the answers

What type of dentition did Archaeopteryx exhibit?

Cuplike thecodont teeth akin to dinosaurs Signup and view all the answers

What adaptation is unique to advanced avian ancestors regarding bone structure?

Hollow pneumatic bones for reduced body weight Signup and view all the answers

Which feature is characteristic of birds, specifically linked to their respiration system?

Single direction airflow pattern Signup and view all the answers

What feature distinguishes Australopithecus afarensis from modern humans?

Sloped forehead Signup and view all the answers

What is a notable skeletal feature of the Australopithecus afarensis skeleton, famously known as Lucy?

Long arms for tree climbing Signup and view all the answers

Which feature is characteristic of Homo erectus compared to earlier hominids?

Downward-pointing nose Signup and view all the answers

Which genus does the garter snake belong to?

Thamnophis Signup and view all the answers

How did the teeth of Australopithecus afarensis differ from those of modern humans?

More sizable and robust Signup and view all the answers

What is the primary habitat of the African spurred tortoise?

Southern edge of the Sahara Desert Signup and view all the answers

What general time frame did Australopithecus afarensis inhabit the Earth?

2 to 3 million years ago Signup and view all the answers

In comparison to Australopithecus afarensis, what does the fossil record suggest about Homo erectus?

It had a larger cranial capacity. Signup and view all the answers

What distinguishes primary feathers from secondary feathers in birds?

Primary feathers are located at the wing tip, secondary feathers are closer to the body. Signup and view all the answers

Which statement is true regarding the usage of images credited to other sources?

Images must be attributed to their original sources. Signup and view all the answers

What does the prominent jaw and larger teeth of Australopithecus afarensis suggest about its lifestyle?

It required a diet of tough plant material. Signup and view all the answers

Which characteristic of Australopithecus afarensis indicates its ability for bipedalism?

Pelvic structure for upright walking Signup and view all the answers

What unique attribute makes the genus Thamnophis notable among reptiles in North America?

It is the most widely distributed reptile genus. Signup and view all the answers

What licensing allows the reproduction or modification of the OpenStax resource?

CC-BY 4.0 International License Signup and view all the answers

Which of the following is true about the African spurred tortoise?

It lives at the southern edge of the Sahara Desert. Signup and view all the answers

How must any changes made to the OpenStax resource be indicated?

By noting the changes in documentation. Signup and view all the answers

Which of these birds provides thrust with its primary feathers?

Hummingbirds Signup and view all the answers

What characteristic applies to both primary and secondary feathers in birds?

They are both vital for flight. Signup and view all the answers

Study Notes

Vertebrates

Vertebrates are a group of animals with a backbone.
They are deuterostomes, possessing a notochord at some stage of their life cycle.
Four common features appear at some point during development of chordates: a notochord, a dorsal hollow nerve cord, pharyngeal slits, and a post-anal tail.
The endostyle is situated in the floor of the pharynx.
Some examples of critically endangered vertebrate species include Siberian tigers, mountain gorillas and harpy eagles.
Critically endangered animals can have their former ranges affected negatively.

Vertebrate Species Examples

Siberian Tiger (Panthera tigris): Critically endangered.
Mountain Gorilla (Gorilla beringei): Critically endangered.
Harpy Eagle (Harpia harpyja): Critically endangered in some regions.

Phylogeny of Chordates

Chordates include vertebrates and invertebrates such as cephalochordates and urochordates..
The image shows the evolutionary relationships among various vertebrate groups.
The chart displays the evolutionary relationship and hypothesized relationship among hominins with reference to modern humans.
The chart shows evolutionary relationships among different hominin species and their hypothesized relation to modern humans.

Key Features of Chordates

Notochord: A flexible rod-like structure that provides support.
Dorsal hollow nerve cord: A tube-like structure that develops into the brain and spinal cord.
Pharyngeal slits: Slits located in the pharynx that can develop into gills or other structures.
Post-anal tail: A tail extending past the anus.

Characteristics of Lancelets

Notochord extends into the head region.
Possess a notochord, a dorsal hollow nerve cord, pharyngeal slits, an endostyle, and a post-anal tail.

Tunicate Characteristics

Larval stage of tunicates possess all chordate features including notochord, dorsal nerve cord, pharyngeal slits and a post-anal tail.
In the adult stage notochord, nerve cord and tail structures disappear.
Presence of pharyngeal slits and endostyle.

Colonial Tunicates

Feed on phytoplankton.
Reproduce with younger female colonies sometimes fertilized by older male colonies.

Subphylum Craniata

Organisms are characterized by the cranium, mandible, additional facial bones.
Dunkleosteus was an example of a fish species from the subphylum.

Vertebrata

Characterized by the backbone structure that runs through the middle of the body.
All vertebrates are in the Craniata clade.
Have a cranium, or skull.
The backbone structure runs through the middle of the body.

Pacific Hagfish

Are scavengers that live in the ocean floor.

Parasitic Sea Lampreys

Attach to lake trout hosts using suction.
Use their rough tongues to rasp flesh from the trout to feed on the trout's blood.

Dunkleosteus

An enormous placoderm fish from the Devonian period.
Measured up to 10 meters in length.
Weighing as much as 3.6 tons.
Its head and neck were armored with heavy bony plates.
No true teeth.
Jaws armed with sharp bony blades.

Hammerhead Sharks

Tend to school during the day and hunt prey at night.

Whale Sharks

Filter-feeders.
Can grow to be over 10 meters long.
Ovoviviparous.

Shark Embryos

Clearly visible through transparent egg cases.
The yolk nourishes the developing embryo.

Stingray and Spotted Ratfish

Stingray blends into the sandy bottom of the ocean floor.
Spotted ratfish swims near the ocean floor.

Sockeye Salmon and Coelacanth

Sockeye salmon and coelacanths are bony fishes in the Osteichthyes clade.
Coelacanths were once thought extinct but were rediscovered in 1938.

Tiktaalik roseae

A recent fossil discovery that suggests an intermediate animal between finned fish and legged tetrapods.
Known as a fishapod.

Salamanders

Most salamanders have legs and a tail.
Respiration varies among species.

Australian Green Tree Frog

Nocturnal predator.
Lives in the canopies of trees near water sources.

Juvenile Frog Metamorphosis

A juvenile frog goes through metamorphosis to become a frog.
Frog develops limbs but tail is still evident.

Paleozoic Era Gondwana

Gondwana formed around 550 million years ago during the Paleozoic Era.
Both Gondwana and Laurentia were situated around the equator.

Amniotic Egg

Key features of the amniotic egg are shown which include the shell, albumen, yolk, yolk sac, amniotic cavity, amnion, embryo, allantois, and chorion.

Skull Comparison of Anapsids, Synapsids and Diapsids

Anapsids have no openings.
Synapsids have one opening.
Diapsids have two openings.

Amniote Evolution

Characteristics of different amniotes and their evolutionary relationships are presented.

Pterosaurs

Pterosaurs (like Quetzalcoatlus) from the Triassic to Cretaceous period.
Not believed capable of powered flight but potentially soared after taking off from cliffs.

Edmontonia and Herrerasaurus/Eoraptor

Edmontonia: an armored dinosaur from the Late Cretaceous period (145.5 to 65.6 million years ago).
Herrerasaurus and Eoraptor: late Triassic saurischian dinosaurs (approximately 230 million years ago).

Siamese Crocodile

Provides parental care for its offspring.

Tuatara

Resembles a lizard but belongs to the Sphenodontidae family.
A distinct lineage from New Zealand.

Jackson's Chameleon

Blends in with its surroundings.

Garter Snake

Belongs to the Thamnophis genus.
Most widely distributed reptile genus in North America.

African Spurred Tortoise

Lives on the southern edge of the Sahara Desert.
Third largest tortoise in the world.

Bird Wing Structure

Primary feathers provide thrust, located at wing tip.
Secondary feathers provide lift, close to the bird body.
Diagrams illustrate bird wing structure.

Bird Pneumatic Bones

Many birds have hollow, pneumatic bones.
This makes flight easier.

Avian Respiration

Avian respiration is an efficient gas exchange system where air flows unidirectionally.
A full ventilation cycle takes two respiratory cycles. This involves the air sacs, lungs, and trachea.

Archaeopteryx & Flight Feathers

Archaeopteryx lived in the late Jurassic period (150 million years ago).
It had cup-like thecodont teeth like a dinosaur, but also had flight feathers similar to modern birds.
Claws on wings are also characteristic, indicating its ancestry.

Shanweiniao cooperorum

A species of Enantiornithes that did not survive past the Cretaceous period.

Mammalian Middle Ear Bones

Bones of the mammalian middle ear are modified from bones of the reptile jaw and skull.
Examples: Malleus, Incus, Stapes.
Derived from articular and quadrate bones.

Cynodonts

Cynodonts (260 million years ago) are the ancestors of modern mammals.
Holes in their jaws suggest whiskers, possibly indicating hair.

Megazostrodon

Likely nocturnal and insectivorous, possibly eating insects.
Possible double jaw hinge present between the dentary and squamosal bones, as well as between the articular and quadrate bones.
Articular and quadrate bones have been assimilated into the middle ear in living mammals.

Platypus (Monotreme) & Echidna (Monotreme)

Platypus possesses a leathery beak and lays eggs.
Echidna is another monotreme (egg-laying mammals) with long hairs modified into spines.

Tasmanian Devil

A marsupial native to Australia.

Tarsier

Smallest primates (about 5 inches long)
The tail is approximately twice the length of the body.
Note the extremely large eyes, each about the same size or larger than their brains.
Also characterized by long hind legs.

Howler Monkey

Native to Central and South America.
Makes a call that sounds like a lion roaring.

Great Apes' Skeletal Structure

All great apes have similar skeletal structures (Gibbons, Humans, Chimpanzees, Gorillas, Orangutans).

White-Cheeked Gibbon

Females and infants are buff-coloured.
Males are black.
This species of Lesser Apes has no tail and relatively large brains.

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Description

This quiz explores vertebrates, focusing on their defining features, examples of critically endangered species, and the phylogeny of chordates. Learn about the evolutionary relationships that shape this diverse group of animals with backbones.