Diversity of Animals II/Ecology Flashcards
What class was the first vertebrates to move onto land?
Amphibia
Give three (3) examples of organisms that were already on land before the amphibians
- Plants
- Snails
- Arthropods
What are four (4) adaptions necessary for vertebrates to become terrestrial?
- Lungs
- Stronger limbs
- Thermoregulatory mechanism
- Reproductive strategies that don’t involve water
Why are stronger limbs required to be terrestrial?
Air is 1,000 times less buoyant than water so strong limbs are necessary to prevent being crushed under own weight.
What causes a large diversity of terrestrial organisms?
There are lots of habitats to move into and adapt to.
What does “amphibia” literally translate to?
Amphi: Both
Bia: (Bio) Lives
Both lives
What are the two (2) stages of a frog?
- Tadpole
2. Adult
What is the diet of a tadpole?
Herbivore
How does the tadpole move around?
Tail for swimming
Where does the tadpole live?
Aquatic
How does the adult frog move?
Legs
What does the adult frog eat?
Carnivore
How does the adult frog breathe?
Lungs
Describe “grasping” by a frog
The male grasps the female stimulating her to release eggs.
How are frog eggs fertilized?
The male releases sperm into the water where the eggs are fertilized.
Why must frog eggs be fertilized in water?
They have a jellycoat without a shell and would desiccate in air.
Describe the skeleton of amphibians
Bony skeleton
How many limbs to amphibians have?
Tetrapods (4 limbs)
Describe the skin of amphibians
Moist skin with mucous glands that are often toxic.
Describe three (3) ways that amphibians undergo gas exchange
- Skin
- Gills
- Lungs
Describe the number of chambers in an amphibian heart
3-chambered heart:
- 2 atria
- 1 ventricle
What does ectothermal mean?
Body temperature is regulated by the environment
How do amphibians regulate their body temperature?
Ectothermal
How can some amphibians hear?
External eardrums for sound carried through the air.
What are four (4) possible causes of the crashes in amphibian populations?
- Habitat alterations
- Global warming
- Acid rain
- Fungal (chytridia) infection
What are three orders of the class Amphibia?
- Caudata (aka Urodela)
- Anura
- Gymnophiona (aka Apoda)
What is the meaning of the word Caudata?
Tailed
What is the meaning of the word Anura?
Without tail
What is the meaning of the word Apoda?
Without feet
What is the meaning of the word Gymnophiona?
Naked Serpent
What are two examples of the Order Caudata?
- Salamanders
2. Newts
What are two examples of the Order Anura?
- Frogs
2. Toads
What is an example of the Order Gymnophiona?
Caecilians
What is the class animals that is the first truly terrestrial animals that can live far from water for their entire lives?
Class/Clade Reptilia
What is characteristic of the skin of Reptiles?
Dry skin covered in scales
What is the purpose of scales on a reptile?
To keep moisture inside their bodies
How do reptiles regulate their body temperature?
Ectothermic
Describe the eggs of reptiles
Covered in a leathery shell to prepare drying
How are reptile eggs fertilized?
Internal fertilization (egg must be fertilized before shell is formed)
Describe the chambers of the heart for most reptiles
3-chambered heart:
- 2 Atria
- 1 partially separated ventricle
What reptiles have a 4-chambered heart?
Order Crocodilla
Describe the lungs of reptiles
More powerful than amphibian lungs
Describe the legs and jaws of reptiles
More powerful than amphibians
What are three (3) Orders of the Class/Clade Reptilia?
- Testudines
- Squamata
- Crocodilla
What is an example of the Order Testudines?
Turtles
What is are three (3) examples of the Order Squamata?
- Lizards
- Snakes
3 Worm lizards
What are two (2) examples of the Order Crocodilla?
- Crocodiles
2. Alligators
Stem (ancestral) reptiles gave rise to what three major lineages of animals?
- Reptiles
- Birds
- Mammals
What class of vertebrates outnumbers all vertebrates except the fishes?
Class/Clade Aves
Which members of Class/Clade Aves have feathers?
All
Describe the legs of Class Aves
Scaled legs
Describe the forelimbs of Class/Clade Aves
Modified for flight, although not all birds can fly.
Why have birds not achieved the diversity of body forms that other terrestrial animals have?
Flight limits the potential body shapes
What is endothermic?
Body temperature is regulated internally
How do birds regulate their body temperature?
Endothermic
Describe the bones of Class/Clade Aves
Hollow with cross struts to make them light yet strong
Do birds have teeth?
No
Describe the tail of birds
Short tail but feather can make it appear long.
Describe the chambers of the heart of Class/Clade Aves
4-chambered heart
What is unique about the female gonad in Class/Clade Aves
Only the left ovary and oviduct are functional
Where does fertilization occur for class/clade Aves?
Internally
Describe the shells of Class/Clade Aves
Hard calcareous shells
Describe the blood cells of Class/Clade Aves
Nucleated red blood cells
What does heterogametic mean?
The gamete can be two different forms (e.g. male mammals have X and Y)
What letters are used to indicate Aves sex chromosomes
ZZ (Male)
ZW (Female)
What is the heterogametic sex in Class/Clade Aves?
Females:
Eggs can be Z or W
What is the significance of Archaeopteryx?
Ancestor of birds that was reptilian (teeth, claws, long bony tail) but also had feathers.
What are four (4) shared traits between modern birds and reptiles?
- Single occipital condyle
- Stapes
- 5-6 bones in lower jaw
- Waste is concentrated uric acid
Where dinosaur was the likely ancestor of bird?
Theropod NOT Pterosaur (e.g. pterodactyl)
What is the consequence of the modern belief that Reptiles and Birds are monophyletic?
It places birds in the Reptile clade
What are the two (non-taxonomic) groups of birds?
- Ratites
2. Carinates
Describe Ratites
Large, flightless birds with a flat sternum and weak pectoral muscles
Describe Carinates
Flying birds with a keeled sternum that gives a large surface area for flight muscle attachment
What are four (4) examples of ratites?
- Ostriches
- Emus
- Rheas
- Kiwi
What is the origin of flightless birds?
All modern-day birds evolved from flying ancestral birds. Flightless birds lost flight secondarily
What is the most diverse class of vertebrates?
Class Mammalia
What is the world’s smallest mammal?
Bumblebee bat (aka Kitti’s hog-nosed bat)
What is the world’s largest mammal?
Blue whales
Describe the appearance of the earliest mammals
Shrew-like
What covers the bodies of mammals?
Hair (reduced in some)
What are three types of glands present in mammals?
- Sweat glands
- Scent glands
- Sebaceous glands
What is the defining characteristic of mammals?
Mammary glands for nursing young (modified sweat glands)
How many occipital condyles attach the skull to the vertebral column in mammals?
two
Describe the jaw of mammals
A single large bone on each side