Quiz 2 Flashcards
How are fossils formed?
When a living organism dies and their remains are quickly buried by sediment
What are the greatest challenges to fossil evidence for evolution?
There are gaps in the fossil record and it’s incomplete because many early forms of life were soft-bodied
What is the Law of Superposition?
Sedimentary layers are deposited in a time sequence, with the oldest on bottom and the youngest on top
How can we reconstruct the sequence of geologic events that have occurred as a site?
Using relative dating principles and the position of layers within rock
Wetlands found in temperate regions characterized by presence of sphagnum moss, typically nutrient poor and acidic with few tree species (mostly tamarack)
Bogs
Wetlands found in temperate regions contain low-growing emergent plants such as cattails as well as shrubs and trees:
Marshes
Herbaceous plants that are characterized by coming up from new seed every year, blooming, setting seed, and then dying
Annuals
What herbaceous plants likely evolved as a result of farming practices common in Europe at the time that settlers from Europe first arrived in North America:
Biennials
Weeds are defined as those plants that are typically characterized as:
Prolific seed producers that thrive in disturbed areas
Why do animals tend to populate edge zones of natural biotic communities?
Because animals find the best supplies of space, shelter, food, and water
What is the phenomenon of animals populating edge zones of natural biotic communities called?
The edge effect
The predictable and orderly changes in the composition or structure of an ecological community
Succession
What is primary succession?
Begins in a virtually lifeless area where soil hasn’t formed yet
Soil develops gradually as rock weathers, and decays from activity of early colonizers like algae and lichens
What is secondary succession?
Existing community is cleared by disturbance that leaves soil intact
Like fire or farming
What does succession ultimately produce?
A climax community, a permanent, self-sustaining community appropriate to the local area
What is a biome?
A community of organisms determined by climate conditions and recognized by the characteristic structure of its dominant vegetation
What are the limiting factors of plant growth?
Nitrogen, potassium, and phosphorus
If a plant species is introduced from outside its native habitat and outcompetes the native plants in the area, it is referred to as:
Invasive species
When an introduced species survives and reproduces in a new environment without impacting the general survival of native species, it is referred to as:
Naturalized species
What is comparative embryology?
The comparison of embryos at different stages of development of different organisms
What do similarities in embryonic development suggest?
Common ancestry
What is an example of comparative embryology?
Gill slits in embryos of many quadrupedal and fish-like organisms
What is oviparity?
Birds, frogs, and most invertebrates hatch eggs
What is viviparity?
Eutherian mammals give birth to live young
What is ovoviviparity?
Certain reptile and sharks produce an egg that hatches inside the body
Describe the holoblastic pattern of cleavage
Entire egg divide into smaller cells in amphibians and mammals
Describe meroblastic pattern of cleavage
Only one part of egg is destined to become embryo, other portion serves as nutrition (embryo) in birds and fish
What do all animals originate from?
Eggs
What is the blastoderm of chick embryos?
Small region of egg that contains yolk-free cytoplasm that gives rise to embryo
What forms before the heart does in chicks?
Islands of blood cells
What does comparative embryology show?
How different adult structures have the same embryonic precursors
Define homologous structures
Features that result from a common ancestor, even if they look different today
What is an example of a homologous structures?
Bat wing and human hand; share the same bones
What kind of evolution are homologous structures?
Divergent evolution
Define divergent evolution
Two or more characteristics have a common evolutionary origin, but have diverged over time
Divergent evolution is also known as…
Adaptive radiation
Characters of divergent evolution can be…
Observable from different species or molecular entities like genes
Define analogous structures
Features that do not have a common ancestor, but may have the same function today
What is an example of analogous structures?
Bird wing and bat wing; perform same function but evolved indendently
What type of evolution are analogous structures?
Convergent evolution
Define convergent evolution
Organisms not related independently evolve similar traits as a result of having to adapt to similar environments/niches
Define vestigial structures
Homologous characters which have lost all or lost if their function through evolution
Vestigial may take…
Various forms such as anatomical structures, behaviors, and biochemical pathways
Vestigial structure have __ _____ _______ and are _________ ____ _________ ___ ______ _____
No known purpose, leftovers from ancestors who needed them
What are examples of vestigial structures?
Wings on flightless birds
Human body hair
Appendix
Leg bones on whales and snakes
Plants and animal cells share…
Most of the same organelles
The closer two organisms are related, ….
The more genes they have in common and the closer their amino acid sequences are
Some genes are…
Wide-spread among organisms
Example of cellular and molecular evidence:
Pax-6 gene; codes for making eye in humans and flies
Examples of sub-optional design
Trachea vs esophagus (can lead to choking)
Human eye (inverted retina; blind spot)
Non-coding DNA
What type of crops/livestock are chosen to reproduce?
Most fit/desirable
Overtime, characteristics in crops/livestock…
Change
Define natural community
An assemblage of plants and animals living together in the same environment
The swamp forest is home to the…
Greatest number of tree species along natural communities in our area
Lowland trees in the swamp forest have what type of roots?
Shallow and wide-spreading
Where is Sedge Meadow found?
Swampy, riverbank, or other wet environments
Define wetlands
Any area either covered by shallow water or containing waterlogged soil where the soil lacks oxygen and grows water-loving plants
List types of wetlands
Marshes, swamps, bogs, fens, wet meadows, temporarily flooded wetlands (seasonal wetlands)
List characteristics of marshes
Composed of open water and standing vegetation like bulrushes and cattails
Soil usually fertile muck
Lack woody plants
List a characteristic of swamps
Containing shrubs and trees:
Alder, dogwood, silver maple
List characteristics of bogs
Dominated by sphagnum moss that holds water
Highly acidic and anoxic
Woody plants like tamarack, high bush blueberries, and glossy buckthorn
Native carnivorous plants like pitcher plant and sundew
List characteristics of fens
Similar to bogs but highly alkaline
Sees and rush dominated
Occurs on alkaline saturated sphagnum and/or marl influenced by groundwater rich in calcium and magnesium carbonates
What is old field succession?
Type of secondary succession that begins with open soil already in place
What does primary succession begin with?
Raw rock surface
List characteristics of the northern coniferous forest
Largest biome
2 layers of vegetation
Populated by needled trees like spruce, fir, and tamarack
What is the diagnostic herbivore of the northern coniferous forest?
Moose
Describe environment of northern coniferous forest
Many bogs dominated by sphagnum
Typically sandy soils
Insectivorous plants like sundew and pitcher plant
Ground dwelling plants like blueberries, bearberries, and leather leaf
When do bogs form?
As rate of decay is slowed by lack of bacteria populations due to cold temperatures, acidic conditions, and low O2 levels
List characteristics of the tundra
Permafrost causing poor drainage
Flat terrain
Grass, sedges, low shrubs (creeping willow), mosses, lichens, etc
Lots of mosquitos
List characteristics of tundras in alpine regions
High altitude
Slightly longer growing seasons
Shorter days
Better drainage on rough terrain
No permafrost
What is the diagnostic herbivore of the tundra?
Reindeer or caribou
What is the top predator of the tundra?
Polar bear
If the precipitation level in the tundra is equivalent to that of the desert, why do marshy environments form?
Permafrost
Short warm season leading to melting water
List characteristics of the temperate deciduous forest
Home biome
Broadleaf production
Moderate temperatures and seasonal patterns
3 layers of vegetation
What is the primary herbivore of the temperate deciduous forest?
White-tailed deer
Why do leaves fall each year in the temperate deciduous forest?
To allow attachment sites to heal and prevent infection during winter months of inactivity
Where is the bulk of organic material in the temperate deciduous found?
Leaf litter
List characteristics of tropical rain forest
550+ species of broadleaf evergreens
Many species, few organisms
7 layers of vegetation
What is the primary predator of the tropical rainforest?
Boa constrictor
Where is the bulk of organic material in the tropical rain forest?
Living things because soil is being leached by heavy rainfall and nutrient poor
List a characteristic of temperate rain forest
Largest trees in the world (firs and hemlocks)
List characteristics of prairies
Mostly native plants, wheat and corn acreage as well
No trees
Flat/rolling terrain
What are prairies?
Climax communities, sustained populations within a stable community no longer undergoing succession
Where is the bulk of biomass in prairies?
Below surface in the root mass, up to 10”
What is the first stage of secondary succession?
Weedfield
What separates prairies from forests?
Less rainfall, fewer woody plants
What is the primary grass of the tall prairie?
Big bluestem
What is the primary herbivore of the prairie?
Bison
How are prairie plants adapted to the region?
Massive grown fibrous roots to trap water to reach the surface or further east, thick and deep roots that penetrate aquifer
How have plants developed habits to reduce evaporation in the prairie?
Leaves vertical
Grass blades roll when dry
Fuzzy hairs protect from desiccation
Thickened sap
Hard-coated seeds
List characteristics of the desert
Bare ground between plants
Cacti
Specialized shrubs
What farming practice common in Europe is believed to have led to the evolution of biennials?
Crop rotation
What are epiphytes?
Plant that grows on other plants
No attachment to ground
Not parasitic on supporting plants
What are lianas?
Vines climb all the way up to the trees to the canopy, especially in tropical rainforest
Important structural difference between tropical and temperate rainforess
How can we prevent the spread of invasives?
Don’t import invasive pests
Don’t release pets into wild
Don’t plant invasives
Both artificial and natural selection involve…
Changes to genes in populations (evolution)
Red and jack pines are…
Early succession of upland forest community
Sugar maple is a part of…
Upper story (canopy) climax community of upland forest community
Hickories are apart of…
Upper story middle succession of upland forest community
Blue beech is a part of…
Under story (2nd) of swamp forest
Beech is a part of…
Upper story (canopy) climax community of upland forest community
Flowering dogwood is a part of…
Under story (2nd) middle and late succession of dry forest community
Yellow birch is a part of…
Canopy of swamp forest
Willows are a part of..:
Shrub Carr
Alders are a a part of…
Shrub Carr
Oaks other than pin are a part of…
Upper story middle succession of upland forest community
Poplars are a part of…
Early succession of dry forest community
Dogwoods other then flowering are a part of…
Shrub Carr
