Tectonic Plates And Species Distribution

Question 0

What occurs when plate margins meet?

Answer 0

Causes:
- volcanoes + eruptions
- earthquakes 
- mountain ranges (can change weather systems!) 
And more ...

Question 1

What are tectonic plates?

Answer 1

• Rigid plates found on the lithosphere (earths crust)
• they move (0-100mm per year)
• made of 7-8 plates and minor plates
• there movement is slow but constant

Question 2

What about tectonic plates in the future?

Answer 2

• currently got separate continents

- in about 250mill. Years time the supercontinent will form again

Question 3

What happened in the history of tectonic plates?

Answer 3

Gondwanaland - supercontinent when all continents were one

• occurred in Permian period (255mill. Years ago)
• great American faunal exchange (GAFE)

Question 4

How are tectonic plates important to biogeography?

Answer 4

• Continental drift established reason for distribution of present day species
• populations of species moved to different areas of the globe via continental drift
• vicariance biogeography
• causes allopatric speciation

Question 5

Why are tectonic plates important?

Answer 5

• They are a large scale issue.
• most severe and immediate issue along side climate change
• they shapes and move our continents
• they influence the distribution of species
• tp changes will massively change species distribution / range

Question 6

What example is there of species distribution changes?

Answer 6

• marsupials
• in Australia and South America
• evolved on Gondwanaland
  Cretaceous period
• population split into 3 in 3 separate land masses
• populations remain on 2 of 3 landmasses (Australia and South America)
  -3rd was Antarctica

Question 7

What do plate tectonics cause as a result of movement in biogeography?

Answer 7

• Distribution / dispersal changes
• isolation of species
• allopatric speciation (geographical isolation of a large interbreeding population)

Question 8

What was the Great American Faunal Exchange (GAFE)?

Answer 8

• occurred when N&S America mixed species
• led to a range of outcomes for different species
• 50% of S.American mammal species derive from immigrant lineages - N. America (didelphis marsupialis)
• 10% if N. American mammal species derive from immigrant lineages - S. America

Question 9

What is continental fusion?

Answer 9

• The opposite of continental drift
• species from 2+ landmasses can mix
  4 possible outcomes
  1. Active competition
  2. Passive replacement
  3. Insinuation
  4. Toleration

Question 10

What is active competition?

Answer 10

• occurs between two species with a similar ecological niche

Question 11

What is passive replacement?

Answer 11

• Occurs when a species replaces another without competition.
• usually chance occurrence
• mainly theoretical but there is some evidence
• South American ungulates (large mammals/hoofed animals) decline around the GAFE seemingly before active competition

Question 12

What is insinuation?

Answer 12

When an invader species finds previously unoccupied ecological niche and inhabits it.

Question 13

What is toleration?

Answer 13

• When one or more species cohabit

- fossils GAFE suggest S. American camel cohabited with a camel-like macrauchenids for 2.5million years

Question 14

What distribution styles are there?

Answer 14

Continuous
- continuous distribution

Discontinuous

• broken distribution
• common distribution (due to tectonic plates)
• geological disjunction
• climatic disjunction
• evolutionary disjunction
• jump distribution disjunction

Question 15

What is geological disjunction?

Answer 15

• Divide of landmasses

- species or genus continues existence on 2+ different landmasses

Question 16

What is climatic disjunction?

Answer 16

Climate splits an existing population into 2+ separate populations

Eg magnoliaceae - split due to Ice ages continental drift and mountain formation

Question 17

What is evolutionary disjunction?

Answer 17

• Occurs when a species evolve from a…
  common ancestor –> disperse–> common ancestor dies –> leaves 2+ isolated species
• eg woody species
  Ficus and acacia
  1. Sonoran and chihuahuan desert N. America
  2. Chilean and Peruvian deserts in S. America

Question 18

What is jump dispersal disjunction?

Answer 18

• individuals move over inhospitable terrain in the course of their lives
• founder individuals start a new self-sustaining population

Natural example:
- 160 plant species in America

Many kore due to human aid (alien species)

Question 19

Why do species move?

Answer 19

• Species require dispersal to colonise new areas if the globe
  Routes include:
• land bridges both permanent and unterupted (berring bridge)
• stepping stones
• islands
  And more I’m sure