Chapter 29: Vertebrates Flashcards
Instinct
adaptation occurs over generations by selection that results in the various behaviors we observe.
Learning
behaviors are the result of each individual animal’s unique life experiences.
Altruism
Actions done by an individual that could possibly hurt themselves but benefit someone else
Kin selection
In acts of altruism, the kin are usually chosen to be the receiver of those actions
Epigenetics
when gene expression is altered due to other gene expression in the genome or environmental factors.
Eusociality
Where 1 female and some males are able to reproduce, some indv can’t reproduce
Males have 100% gene transmission
Chordates
Notochord
Dorsal hollow nerve chord
Pharyngeal slits
Post anal tail
Notochord
Flexible, rod-shaped structure
Found in the embryonic stage of all chordates
Provides skeletal support
NOT in post natal, instead it’s a vertebral column
Notochord vertebrates
Delete
Dorsal hollow nerve cord
Eventually develops into the brain and spinal cord (CNS)
pharyngeal slits
Openings in the pharynx
aquatic organisms: allow for the exit of water that enters the mouth during feeding
Invertebrate chordates: to filter food out of the water that enters the mouth
Vertebrate fishes: modified into gills, and in jawed fishes into jaws.
tetrapods: modified into components of the ears & tonsils
Post anal tail
Posterior elongation of the body, extending beyond the anus
contains skeletal structures & muscles
In aquatic organisms: maintains this structure to aid in locomotion.
In some terrestrial vertebrates: tails help with balance, courting, and signaling.
In humans: is a vestigial structure
Chordate groups
Urochordata
Cephalochordata
Craniata
Vertebrata
Urochordata
Called tunicates
tunic covering is composed of a cellulose-like carbohydrate material
In adult form: does not possess a notochord, dorsal hollow nerve cord, or post-anal tail BUT larval stage does
Do have pharyngeal slits in both larval & adult stages.
Cephalochordata
Small filter feeders
Possess all of the chordate characteristics in the adult form (embryonic form too)
notochord: extends into the head
Extant members are the lancelets, named for their blade-like shape
Live buried in sand at the bottom of warm temperate & seas
Craniata
Have cranium, jaw, and facial bones
Bilaterally symmetrical
Includes: the hagfishes, which have a cranium, but lack a backbone & ALL of the vertebrates
Vertebrates
Have all 4 characteristics of chordates, BUT they also have a vertebral column composed of cartilage and bone is derived from the notochord (only present in the embryonic stage) during development.
Apparently more closely related to lancelets than tunicates.
Vertebrate groups
Fishes
Amphibians
Reptiles
Birds
Mammals
•PrimatesCutaneous respiration
In amphibians
oxygens/carbon dioxide exchange that can happen through the skin
Tetrapods
Literally means 4 foot animals
Evolved limb for support
Oviparous
mother births a fertilized egg, which hatches external to her body
Ovoviviparous
Eggs are very close to hatching inside of parents body
Viviparous
Live birth, like humans
In reptiles
Fishes
2 kinds: Jawless and jawed fishes
Vertebrates
Jawless fishes
Include hagfishes and lampreys
Not ‘true vertebrates’ – the notochord fails to completely develop into a vertebral column
Lampreys
Similar to hagfishes in size/shape
But possess a vertebral column
many are ectoparasites
Jawless fish
Hagfishes
Eel-like scavengers live on the ocean floor
Are detritivores
Jawless fish
Jawed fishes
Possess sets of paired fins
Jaw evolution allows the expansion of food sources
Belong to either the Chondrichthyes and Osteichtyes groups
Chondrichthyes
Cartilaginous fish Have skeletons made of cartilage Evolved during the early-mid Devonian pd. Live mostly in marine habitats Include sharks, rays, and skates. Most are Oviparous, some Viviparous
Osteichthyes
Bony fish Have skeletons made of bones Have a swim bladder to assist with buoyancy control Species evolved to be marine/freshwater Include trout, mani and angelfish
Amphibians
Had to deal w gravity and how to receive oxygen
Tetrapod and cutaneous respiration adaptation
Reptiles
Tetrapods
Lay enclosed eggs
Viviparous or ovoviviparous
Crocodiles, turtles, snakes, lizards
Birds
Pneumatic bones (hollow) to reduce weight
Feather to direct airflow
Lack urinary bladder (water in cloaca)
Cross-current exchange system
Mammals
Sebaceous glands
Jaw, teeth, 4 chambered heart, gestation, milk for young
Monotremes, Marsupials, Eutherian mamm
Primates
Are mammals Adaptations for living in trees: Rotating Shoulder joint Big toe separation Stereotypic vision Larger brains Claws to flattened nails One offspring per pregnancy
Marsupials
characterized by giving live birth, but continued development in an external pouch
Eutherian mammals
placental mammals
have internal development with a placental structure for nutrients/gas exchange
What aspects of animal development do genes affect?
Sex/morphology
Level of dominance
Behavior patterns
Fish that can develo into different sexes
Blue headed wrasse
Clownfish
Mating strategies
Dom males hold territory for females or fight
Sneaker males hang around dom make territory to access females
Gene expression
Can be altered in both early and later life experiences
Due to genetics or environment
Other genes within a genome can regulate other genes within genome
Advantages to grouping
Protection from predators
Protection from extreme environments/assistance with homeostasis
Assistance with food acquisition
Disadvantages to grouping
Increased competition for food Increased risk of disease transmission Greater conspicuousness to predators Cuckoldry: indv living together Cannibalism of young
