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202 Cards in this Set
- Front
- Back
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lower vertebrate
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primitive vertebrate (ex: fishes)
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higher vertebrate
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advanced vertebrate (ex: mammals)
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Chordate characteristic
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1. notochord
2. dorsal nerve chord 3. pharyngeal gill slits or gill pouches 4. post anal tail |
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Notochord
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-rod-like structure made of semi-rigid group of cells surrounded by fibrous and elastic sheath
-axis for muscles to move -ventral to dorsal nerve chord -replaced by vertebral column in advanced vertebrates |
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Dorsal Nerve Chord
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-dorsal to notochord; tubular
-anterior end becomes brain; posterior portion becomes spinal chord -normally protected by bone i.e. skull and vertebral column |
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Gill Slits
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-pharyngeal cavity to outside of body
-pharyngeal refers to pharynx behind mouth cavity -used for respiration & feeding in lower vertebrates -gill pouchs form in advanced verts as grooves but don't open |
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Post Anal Tail
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functions in locomotion in many lower vertebrates
Occurs in embryonic development of all vertebrates even humans. |
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Other common characteristics of chordates (4)
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1. segmented muscle masses
2. endoskeleton of muscle and bone 3. bilateral symmetry 4. closed circulatory system with ventrally located heart blood is circulated in vessels |
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# of living species of vertebrates
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50,000 species
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Fish Species
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24,000 species
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Bird species
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9,000 species
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Reptiles
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7,000 species
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Mammals
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4,600 species
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Amphibians
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4,200 species (this number is in flux b/c new species are discovered daily)
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Hagfish
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Most primitive living vertebrate
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Characteristic of hagfish (5)
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1. notochord through life
2. fibrous/cartilaginous skeleton (not bony) 3. no jaws 4. no paired appendages 5. poorly developed brain and reproductive system |
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Terrestrial Enviornments
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-various temperatures: tropical => artic
-varous humiditites rain forrests => deserts |
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Aquatic Enviornments
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Marine, Freshwater, and Brackish
-some are capable of changing enviornments i.e. marine to fresh (ex: salmon, Americal eel) -or some inhabit both terrstrial and aquatic enviornments (ex: many amphibians, turtles, marine iguanas, sea birds, seals, sea lions etc) |
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Gonochoristic
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Animals with separate sexes
Most vertebrates are gonochoristic |
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Hermaphroditic
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-Simultaneous: both sexes at the same time (ex: some fish)
-Sequential: change sex during life (ex: some fish-coral reef, possibly one amphibian) |
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Unisex Vertebrates
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Egg develops into female without fertilization. Ex: some fish, amphibians, and reptiles
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Oldest Vertebrate Fossil
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indicates that vertebrates have been on Eart for ~ 500 million years
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A newly acquired trait or a characteristic is called what?
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apomorphic
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A characteristic possessed by all organisms in a particular clade (or group) is called a ______ characteristic.
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shared
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The tunicate is a member of what clade?
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Olfactores
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Balanoglossus (acorn worm) is a member of which clade?
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Hemichordata
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Amphioxus is a member of which clade?
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Cephalochordata
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Name 1 of the 4 chordate features.
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post-anal tail
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Which specimen that we looked as is the oldest extant chordate most closely related to vertebrates?
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Amphioxus (lancelet)
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What mineral makes teeth harder than bone and helps preserve them?
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enamel
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Teeth are a great clue to WHAT about an animal?
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diet
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What are Conodonts?
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extinct chordates whose teeth are found as fossils
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What is the mechanism enabling the diversification and evolution of organisms that Darwin wrote about?
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...
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What characteristics distinguish reptilian teeth from those of mammals? (In particular, how they are replaced and how the teeth of the upper and lower jaws fit together.)
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reptile teeth protrude and clamp together
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Where did the author make his great discovery of the tritheledont?
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Nova Scotla
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What is the difference between derived and primitive characteristics?
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derived are new and primitve are already established
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Teeth originally arose for what function?
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to eat things bigger than their mouths
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In what type of water did the more advanced fishes evolve - fresh or salt water?
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fresh
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In the marine environment, where can the greatest diversity of fishes be found?
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coral reef
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Lamprey are in what specific subclade of Agnatha?
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Cephalaspidomorphi
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Besides a notochord, what else do we share with amphioxus?
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dorsal nerve chord, post anal tail, pharegneal gill slits
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T/F-our bodies are segmented?
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true
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How do sharks maintain their position in the water column?
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liver oils
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Which clade is the hagfish in?
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agnatha
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Rat fish (Chimera) are in what specific subclade of Chondrichthyes?
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holocephali
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What is the term for a fish that is born in freshwater lives in salt water and returns to freshwater to breed?
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anadromous
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Why is a two-chambered heart OK for fish?
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located close to gills
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What is the specialization of the shark (or ray) intestine that increases surface area for absorption?
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spiracle
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What is the organ in sharks (and rays) that helps to regulate salt excretion?
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rectal gland
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What are our intervertebral discs derived from?
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notochord
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According to the author, our skulls are made of what 3 fundamental parts?
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plates rods and blocks
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Of the three FUNDAMENTAL parts of the skull described in Chapter 5 of "Your Inner Fish", which parts cover the brain and which part has many arteries and nerves running through them?
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blocks...
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A single branch of which TWO cranial nerves can carry information about sensation and action?
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trigmmenal and facil...
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What cranial nerve derives from the 1st arch?
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trigemneal nerve...
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How do salmon find their natal stream?
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smell
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Name one of the characteristics that distinguish Agnatha from Gnathostomata.
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they are jawless
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Which clade contains all of the ray-finned fishes?
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Actinopterygii
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About how many extant species of teleosts are there?
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21,000
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A fish with cycloid scales, abbreivate heterocercal tail that can gulp air and live in water with low oxygen is a ______.
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lung fish
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Most primitive bony fish have what type of swim bladder?
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oil-filled
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Name the two clades within Osteichthyes.
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Sarcopetrygii and Actinopterygii
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What is a primitive scale that can be found in gar and sturgeon?
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Ganiod
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Fish scales originate from what tissue?
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dermal
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What is the function of the swim bladder?
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maintain water column
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List two unique (or specialized) characteristics of the coelacanth.
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rostral organ - electrosensory system
intercrainal joint - allow anterior poriton of the cranium to swing upwards |
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What characteristic does a coelacanth share with tetrapods?
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paired fins move in a synchronized tetrapod-like pattern
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The fish that has double vertical bars along the side, is an insectivore, is the most common "bream" and the male guards eggs is the ______?
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...
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The two subclades of Neopterygii are ______ and ______?
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Holostei and Teleostei
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The only ovoviviparous freshwater fish in AL is the ______.
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mosquito fish
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What is the modified anal fin of the males called (From #14 above)?
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gonopodium
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The male guards the eggs after fertilization in which fish?
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seahorse
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Which darter is endemic to AL, is very pollution-sensitive, and has 8 blackish saddles along its dorsal surface?
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alabama darter
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The type of swim bladder that does not retain a connection with the gut and is primarily found in more advanced fishes is a ______ swim bladder.
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gas bladder
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The ______ darter is more pollution tolerant than other members in its group?
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blackbanded
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gonopodium
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anal fin = penis
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Jean-Baptiste Lamark
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(1744-1829) French Naturalist, 1st person to popularize concept that organisms changed over time-before Darwin. Theory of Inheritance of Aquired Characteristics published 1809 ("Lamarckism)
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Theory of Inheritance of Aquired Characteristics
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1. animals naturally progress towards higher form, lose characteristics that are not needed and gain useful ones
2. changes aquired in animal's lifetime were passed on to their offspring (i.e. giraffe's neck) *1st popular theory suggesting animals evolve and provided a partial mechanism* |
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Charles Darwin
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(1809-) British Naturalist, wealthy family, good schooling, studied medicine, went to Cambridge to be a clergyman. Henslow recommended position on Beagle (5 year expedition)
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Charles Lyell
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"Principles of Geology" hypothesized that geological formations we currently see resulted form very slow/gradual geological processes, possiably over millions of years.
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Galapagos Islands
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isolated group of islands, volcanic=new, many unique species that were similar but different from mainland species. (ex: iguanas and finches)
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Alfred Wallace
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Inspired by Darwin's 5 yrs journey, explored regions of the Amazon River. Explored Malaysia and Indonesia. *essay presented jointly with Darwin's
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On the Origin of Species by Means of Natural Selection
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1859...23 years after his trip on the Beagle, Darwin's book regarding natural selection. All copies printed sold on 1st day!
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Contributions to the Theory of Natural Selection
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1870 Alfred Wallace's book
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Henry Huxley
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strong supporter of Darwin's work. Referred to as "Darwin's Bulldog"
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Theories in Darwin's Book (5)
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1. structure of species not static
2. change is gradual and continous 3. "common descent" 4. "survival of the fittest" 5. "Natural selection" |
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Structure of Species not static
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organisms can evolve over generations, proposed earlier by Lamarck
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Change is organisms appears ____
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______ & gradual and continuous
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Common Descent
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similar organisms may be derived from a common ancestor
*Helped account for similarites among organisms* |
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Survival of the Fittest
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more individuals in a species will be produce than survive so only the "fit" survive
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Thomas Malthus
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orginally proposed Survival of the Fittest in "Essay on the Principle of Population" Hypothesized that human population growth would outrun food supply
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Natural Selection
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Nature selects individuals with certain advantageous characteristics. Individuals with characteristics survive and reproduce.
*Helped account for DIVERSITY* |
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Gregor Mendel
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"Mendelian Genetics" work provided a genetic basis/mechanism for biological changes in species.
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Evolution
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refers to changes that occur in the genetic composition of a species over time, results in altered GENOTYPE which may not lead to altered phenotype
(ex: sexual reprod, genetic recombination, point mutations) |
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Fitness
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refers to an organism's ability to survive and successfully reproduce.Genetic change may increase/decrease/not change an organisms fitness. *Change may not always be advantageous)
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"Natural Selection"
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"selective forces" in enviornment act to favor individuals with certain characteristics.
Individual's with certain PHENOTYPES are better capable of surviving and producing more offspring in certain enviornments. |
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"Selective Forces"
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examples: food availiablity, predation, competition, temperature etc.
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Examples of Evidence to Support Evolution (7)
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1. human selection
2. antibotic resistance of bacteria 3. fossil record 4. comparative anatomy 5. comparative physiology 6. comparative embryology 7. molecular genetics |
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Artificial or Human Selection
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The selective breeding of certain animals by humans. (ex: agricultural livestock, dogs, cats, etc)
Reveals: species can change and certain traits can be "selected" |
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Antibiotic Resistance of Bacteria
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First antibiotics were produced 1940's and they disrupted cell walls of bacteria. Bacteria strains are evolving resistance to current antibiotics.(ex: vancomycin)
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Fossils
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remnants or impressions of organisms preserved in sediment. Very rare, organism must be rapidly buried-blocks decomp of organism. Some cases minerals replace hard structures (bones) or a cast is formed.
*Strata fossils are found in are used in dating techniques |
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General Indications from Fossil Record
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1. many species have gone extinct
2. abundance and variety of animals varies with time 3. some represent ancestrial forms of modern animals 4. some appear to represent transitional forms b/w major groups of animals 5. suggest gradual transition over time |
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Archaeopteryx
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oldest bird in fossil record, BIRD WITH REPTILIAN CHARACTERISTICS
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Homologous Structures
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similar structures in different species, and these structures have same embryonic origin.
(ex: homologous limb bones in vertebrates- bones in front flippers or whales homologous to finger and arm bones in other mammals) |
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Analogous Structures
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structures which may be similar in structure or function but are of different embryological origin (ex: insect wing and bird wing)
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Comparative Physiology
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Homologous physiological systems and molecules in different species. (ex: steroid hormones in various vertebrates are similar or identical and often have similar function.)
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Comparative Embryology
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Early stages of embryonic development of various vertebrates show many similarities. Example some structures which are not present in adults may develop and then degenerate in embryos (i.e. human gills and tails)
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Molecular Genetics
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Examination of molecular genetics allows genetic comparison of the relatedness of specific animals.
Human genome project has generated info suggesting hypothesized evolution of the various chromosomes. |
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"Phyletic Gradualism"
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Darwin's theory that evolution of a species was a very gradual process.
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"Punctuated Equilibrium"
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Theory proposed in 1972 by ELDREDGE AND GOULD stating evolution of organisms may occur in jumps followed by relatively static phases.
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"Species" Traditional Definition
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Mayr 1942:
a) group of individuals with similar characteristics b) capable of interbreeding c) reproductively isolated from similar groups |
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"Species" Modern Definition
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"genetically distinct" group of organisms which is also "genetically isolated" from other groups
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Allopatric Speciation
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Subpopulations are physically separated from one another so each subpopulation evolves on its own in a different environment and eventually becomes genetically distinct.
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Sympatric Speciation
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Subpopulations may becomes isolated due to ecological or behavioral differences. (ex: different niches same location-ground/tree limbs, noctural/diurnal)
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Examples of Speciation: Finches
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Darwin's finches on Galapago's Island: 14 species evolved from single species from South America. Hypothesized to be isolated on island then adapted to specific niches, genetic analysis support also (ex: beak size varies on niche/diet)
ALLOPATRIC & SYMPATRIC SPECIATION |
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Ex. of Sympatric; Lake Baikal Sculpins
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Lake Scullpin: 25 million years old, largest and one of oldest lakes in the world, rifts of seismic activity. Contains 20% unfrozen freshwater.
Many closely related species of sculpin fish occur in lake, but occur no where else in the world |
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"Systematics"
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grouping of organisms
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Why group organisms? (2)
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1. Grouping can provide generalizations, animals are grouped according to similarites.
2. Grouping can provide insight on relatedness of animals. |
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Carolus Linnaeus
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One of 1st systematists (person who classifies living organisms). Published "Systema Naturae" attempted to classify all known plants and animals based on their morphology.
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"taxa"
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Linnaeus, heirachical system of categories
Kingdom, Phylum, Class, Order, Family, Genus, Species |
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"Binomial Nomenclature"
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Linnaeus- two names for the species names
"genus" & "specific epithet" |
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Domestic Dog Species Name
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Canis familiaris
genus = Canis specific epithet = familiaris species = Canis familiaris |
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Humans Species Name
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Homo sapiens
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Classification method
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grouping of organisms is based on organism's "characteristics"
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"Primitive" Characteristic
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Characteristics hypothesized to be same as ancestral characteristics. (ex: mammals w/ 4 limbs: can be found in more primative vert groups like reptiles and amphibians)
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"Derived" Characteristic
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Characteristic hypothesized to be newly aquired, new characteristic of a group is not found in ancestral groups. (ex: mammal hair because doesn't appear in more primative verts)
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Traditional Systematics
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based on analysis of animal characteristics, but certain characteristics may be given more "weight" than others
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Cladistics
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Groups of organisms based only on "shared derived" characteristics, that is characteristics that appear to be newly derived and that are shared by all members of the group.
EQUALLY WEIGHED, groups on how recently they had a common ancestor |
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monophyletic or clades
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A group that contains all members of a group that are hypothsized to be derived from a specific common ancestor.
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Cladograms
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generated by cladistics analysis, diagram of different clades
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Paraphyletic group
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Groups that do not contain all members hypothesized to be derived from a specific common ancestor. (ex: turtles)
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Radiometric dating
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techniques developed & refined b/w 1911-1950's. Provided a method of accurately dating rocks and fossils. Radioactive isotopes are trapped in rock and can be used to date with half life.
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Potassium- 40
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half life = 1.28 billion years
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Carbon- 14
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Found in organic material, so useful for dating organic material > 60,000 years old.
Half life = 5,730 years |
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Earth's Age
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~4.5 Billion years old
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4 Major Eras of Earth
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1. Precambian Era
2. Paleozoic Era 3. Mesozoic Era 4. Cenozoic Era |
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Precambian Era
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prior 570 million years ago, life 1st appears in fossil record
OLDEST FOSSILS ARE PROKARYOTES: Cyanobacteria ~3.5 billion years old |
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Paleozoic era 6 periods
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1. Cambrian
2. Ordovician 3. Silurian 4. Devonian 5. Carboniferous 6. Permian |
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Cambrian Period
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505-570 million years ago, 1st chordates fossils, 1st vertebrate fossil
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Cambrian Explosion
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A great increase in number of invertebrates. Suggested due to increase in oxygen in the seas by photosynthesis by cyanobacteria.
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Pikaia
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one of oldest known chordates, 535 million years ago found in Burgess Shale.
1st CHORDATE FOSSIL showed notochord, segmented muscles, head and tail regions |
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Ostracoderms
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group of jawless marine fishes, 1st VERTEBRATE FOSSILS 500 million years ago
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Ordovivian Period
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440-505 million years ago, abundant marine invertebrates, 1ST TERRESTRIAL PLANTS IN FOSSIL RECORD
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Silurian Period
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407-440 million years ago, 1ST JAWED FISHES APPEAR
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Devonian Period
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360-407 million years ago, "AGE OF FISHES" saltwater and freshwater fish are abundant, ostracoderms becoming extinct, 1st forrests, 1st winged insects, 1ST AMPHIBIANS
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Carboniferous Period
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286-360 million years ago, large forrests than now are fossil fuel, radiation of amphibians, FIRST REPTILES, 1ST AMNOITIC EGG, giant insects
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Permian Period
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245-286 million years ago, radiation of reptiles, 1st mammal like reptiles, extinction of many amphibians, A mass extinction at end of period 90% marine inverts & 70% of terrestrial species extinct
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Mesozoic Era (Periods 3)
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AGE OF REPTILES Periods:
1. Triassic 2. Jurassic 3. Cretaceous |
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Triassic Period
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200-245 million years ago, reptiles are abundant, 1st turtles, conifers are dominant, 1st flowering plant, 1ST DINOSAURS AND MAMMALS APPEAR IN FOSSIL RECORD
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Jurassic Period
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144-200 million years ago, dinosaurs abundant, marine reptiles abundant, flying reptiles abundant, 1ST BIRD APPEARS IN FOSSIL RECORD
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Archaeopteryx
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oldest bird fossil
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Cretaceous Period
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66-144 million years ago, climax of dinos, giant marine lizards and turtles, mass extinction at end of period
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K/T Mass Extinction
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end of Cretaceous period there was a mass extinction of many vertebrates and invertebrates, including dinosaurs. Hypothesized that huge asteroid hit and caused a large dust cloud.
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Cenozoic Era (periods 2)
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66 million years ago-present, AGE OF MAMMALS, Periods:
1. Tertiary 2. Quaternary each with "epochs" subdivisions |
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Tertiary Period
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1.7-66 million years ago, 5 epochs, 1st placental mammals then radiate, bird species radiate, some large carnivorous birds - Diatryma
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Quaternary Period
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1.7 million years ago-present, 2 subdivisions Pleistocene and Holocene
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Pleistocene Epoch
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4 ice ages, climate change, extinction of many large mammals, 1st human and human-like fossils are found
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Most Recent Ice Age
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height 18,000 million years ago and ended 10,000 years ago
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Holocene Epoch
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10,000 years ago-present, growth in human civilization and society
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"Theory of Continental Drift"
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1912, Alfred Weneger noticed a close fit between South America and Africa, similar fossil and geological strata, mechanism in which they moved was unknown, suggested supercontinent
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"Plate Tectonics"
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earths crust is made of rocky plates which float on material in earths mantle, provided mechanism for gradual movements
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Evidence of Plate Tectonics (3)
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a. fossil and strata are similar where hypothesized to be connected
b. paleomagnetic infrences- orientation of magnetic material is fixed within rocks c. actual movements can be monitored |
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Sea Floor Spreading
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two plates are moving apart from each other, accumulation of new sea floor due to magma swelling up
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Convergence
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one plate is pushed up over another, can form mountains, marine fossils found at tops of mountains
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Pangaea
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during triassic period, all continents were hypothesized to be coalesced into one supercontinent. Broke into Laurasia and Gondwana end of Mesozoic Era
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Wallace Line
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certain types of animals were restricted to certain regions and that in certain areas of the world, there could be distinct shifts in the type of animals even though climate and enviornment were similar
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Animal Kingdom
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Protostomes and Deuterostomes
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Protostomes
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Annelida (worms)
Mollusca (snails) Arthropoda (insects) |
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Deuterostomes (subgroups 2)
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Echinodermata (sea stars)
Hemichordata (acorn worms) Chordata 2 sub groups UROCHORDATA & CEPHALOCHORDATA |
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Urochordata
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"tunicates" & "sea quirts" 4 classes and ~ 3,000 species, all marine, solitary or colonial, adults-sessile or pelagic, filter feeders, hermaphroditic, external fertlization,
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Why are adult tunicates considered chordates?
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Because swimming larva have chordate characteristics; notochord, dorsal tubular nerve chord, pharnygeal slits, post anal tail, brain, eye, and organ to balance
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Paedomorphosis/Neoteny
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retention of larval characteristics in adult hood
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Cephalochordata
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"amphioxus" & "lancelet" small, marine, separate sexes, all 4 chordate characteristics, segmented body and muscles, closed circulatory, filter feed
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Ostracoderms
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Oldest vertebrates in the fossil record, marine, late Cambrian/early Ordovician, jawless, bony body plates, head w/ brain, pineal eye, 1 nostril, no jaws, slit like mouth- no teeth, filter feeder
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Hagfish
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most primitive extant vertebrat
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Agnathans
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Jawless Fishes, hagfish and lamprey
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Gnathostome
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Jawed Fishes
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Chondrichthyes (2 subgroups)
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jawed fishes with cartilaginous skeleton
1. elasmobranches 2. holocephali |
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Elasmobranches
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skarks, skates, rays
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Holocephali
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chimeras (ratfish)
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Osteichthyes (2 subgroups)
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jawed fishes with bony skeletons
1. Sarcoptergii 2. Actinopterygii |
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Sarcopterygii
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flesh-or lobed-finned fishes
1. coelacanth 2. Lungfishes |
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Actinopterygii (2 subgroups)
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ray-finned fishes
1. Chondrostei 2. Neopterygii |
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Chondrostei
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most primitive ray-finned fish, paraphyletic group, very few still exist ex)sturgeon, paddlefish, bicher
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Neopterygii (2 subgroups)
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more modern ray finned fish
1. early neopterygii- "intermediate ray finned fish" 2. Teleostei- advanced ray finned fish |
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Teleostei
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advanced ray finned fish; most common fish are teleostei
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Gnathostomes
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jawed vertebrates
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Jaws
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major advancement, braced against crainium but movable, increase feeding capabilities, may have developed from gill arches
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First Jawed Vertebrates
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fossils found in sediment from Silurian, also had paired fins
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Acanthodians
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first jawed fishes in fossil record, name refers to stout spines
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Placoderms
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heavy armored body, jawed fish, extinct
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Chondrichthyes
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sharks, skates, rays, and chimeras
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Cladoselache
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ancient group of shark like chondrichthyians from the Devonian and became extinct during Carboniferous
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Chondrichthyes-Morphology
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jawed fish, cartilaginous skeletons, paired fins, heteroceral tail, placoid scales, mucous gland, jaws not attached to cranium, no gas bladder
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Chondrichthyes- Nervous System
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brain with lobes, 10 crainal nerves, 3 pairs of semicircular canals, lateral line, olfaction, sensory pits act as electroreceptors
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Sharks eyes accomodate
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lens move forward and backward to focus on near versus far objects
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Chondrichthyes- Digestive
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advanced, spiral valve to slow passage of food
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Chondrichthyes- Circulatory
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2 chambered heart, blood ->heart->gills->body
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Rectal gland
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used to secrete concentrated salt solution into cloaca. helps regulate salt concentration in blood and body fluids
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Chondrichthyes- Reproduction
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Gonochoristic, paired gonads, duct connect to cloaca, internal fertilization
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Oviparous
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produces eggs; embryo and nutrients are sealed in egg case and then released into water
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Ovoviviparous
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live- bearing, embryo and nutrients are deposited in oviduct and can be surrounded by a thin egg case, embryos develop in the oviduct
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Viviparous
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direct connection between mother and embryo
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