Lecture 4: January 17th

Question 1

Northern grouse adaptations

Answer 1

• white for insulation and camoflauge
• feathered legs, feet and toes
• both male and female turn white in the winter.

Question 2

Tundra challenges for plants

Answer 2

• high winds with abrasive particles
• cold temperatures
• reduced growing season, less than 140 days
• permafrost
• not much decomp so limited nutrients. Saxifrage is very common

Question 3

Cold hardiness

Answer 3

plant version of freeze tolerance. Tamaracks tolerate up to -80* celsius

Question 4

Ferns

Answer 4

Moonwart, tiny fern the size of a dime. Being very small is an adaptation of plants for the cold environment. Dwarf birch, arctic willow and labrador willow exhibit dwarfism.

Question 5

Genotypic dwarfism

Answer 5

Size is fixed genetically, ex dwarf labrador

Question 6

Phenotypic dwarfism

Answer 6

when a plant grows larger in southern climates than northern. Size depends on the environment, not genetically fixed. White spruce, dwarf birch

Question 7

Crowberry

Answer 7

creeping, sprawling growth. the outside of the plant might suffer due to wind and cold, but the shape protects the inner part of the plant

Question 8

Heath plants

Answer 8

ex Labrador tea. Retain evergreen leaves, they are masters at surviving tough environments. they grow new ones in the summer when the conditions are more favourable

Question 9

Anthocyanin

Answer 9

dark colors abosrb warmer wavelenghts of light. Prickly saxifrage have this feature, the hairy underside prevents desiccation (drying out)

Question 10

Willow flowers

Answer 10

hairs help them to stay warmer by absorbing incoming energy from the sun, and trap outgoing heat. This is called the greenhouse effect. Polar bears also do this, their skin is black and retains heat. The hair is white and behaves in a similar way.

Question 11

White spruce

Answer 11

most northern spruce tree in Ontario. They can reproduce by seed and vegetatively by layering. Lower branch touches the ground, sprouts roots, then another tree grows. These are giants in the tundra. Phenotypic

Question 12

Layering

Answer 12

how white spruce reproduce

Question 13

American Tree sparrow

Answer 13

ground nesting sparrows in the tundra

Question 14

Allens rule

Answer 14

small extremities to help combat the cold

Question 15

Bergmann’s rule

Answer 15

surface area to volume ratio is conducive, plump rotund body retains body heat

Question 16

Meadow voles

Answer 16

1/3 animals that actually hibernate. Undergo the greatest population cycles of any mammal in the world. The population fluctuates as these mammals are food for arcitc foxes and birds of prey.

Question 17

Short Eared Owls

Answer 17

ground nesting birds, live in areas that small animals are abundant

Question 18

Snowy owls

Answer 18

dark feathers mean its a young owl that was hatched this year. the young females are darkest of all.

Question 19

Indemic Species

Answer 19

only found in one geographic location. HB indemic is confined to the edge of the hudson bay, ex the lepage wild flower

Question 20

Hbl Limits

Answer 20

Southern limit is the tree line, northern limit is the boreal forest. James bay on the east, boreal forest on the west

Question 21

hbl Average temp

Answer 21

-3* - -6*, colder closer to the tree line.

Question 22

Peat

Answer 22

organic soil, made by sphagnum dying and stuff growing on top of the decomposition. The dead part is called the peat. When peat is greater than 45cm thick and wet, it is called muskeg

Question 23

hbl black spruce and tamarack

Answer 23

not dwarves here, but stunted in growth form.

Question 24

Bogs

Answer 24

a true bog receives water nutrients only from rainfall, no rivers or water flow. Has sphagnum moss.

Question 25

Fens

Answer 25

receive nutrients from flowing ground water. Sedges often dominate sphagnums.

Question 26

How do sphagnums form?

Answer 26

• water
• lake fill: the form that peatlands begin to grow
• sedges often start the lake fill, colonize and grow out into the water
• sphagnum moss starts growing around the sedges, spreads and dominates.