Cycle 11: Ecology in the Anthropocene

Question 1

Anthropocene

Answer 1

The anthropocene is the current geological age in which human activity has been the dominant influence on climate and the environment.

Question 2

Tipping point

Answer 2

The tipping point has been set at 1.5 Degree Celsius Increase and describes of no return from climate change.

Question 3

Virtual water

Answer 3

Water used to produce the goods and services others need and enjoy.

Question 4

Industrial melanisation

Answer 4

Anthropocene started with the industrial revolution.
The increase in soot and dust caused by the coal fires darkened the tree trunks. This caused white moths to be easily spotted by predators. So only the dark winged survived this predation. This is why we see an increase in dark coloured moths in industrial areas, and white coloured moths in areas with no pollution. Demonstrates an adaptation.

Question 5

Asynchrony

Answer 5

Species following different environmental cues and migrate at different times
- herbivore and its’ host plant
- Host plant comes out at different time than herbivore migrates
- Herbivore arrives → no food source

Example: Monarch + Red Admiral Butterflies
- Arrived in large numbers due to high temperatures and unusual wind patterns in April, 2019
- Red admiral: semi-tropical, migrates in summer
- Food source was above ground, successful oviposition
- Temperature dropped → larvae died
Monarch:
- Arrived, couldn’t lay eggs
- Milkweed had not come out yet → Died

Describes the migrating species not in the right timing with food source.

Question 6

Capacity to displace

Answer 6

Plants efficacy of speed dispersal (birds and wind dispersal)
Plants - Efficacy of seed dispersal:
- Plants cannot run away
- Birds eat seeds, disperse in different areas
- Wind dispersal - types of seeds

Animals - mobility (speed and how they move):
- Eg turtles cannot move quickly
- However, climate change is gradual
- Birds can fly very long distances
- Some animals use other animals to help them move

Question 7

Hybridization

Answer 7

The process of combining different varieties of organisms to create a hybrid.
Possible consequence: hybridization
- Immigrant may gain genes allowing them to survive in new environment
- Gain of diversity

Question 8

Migrant species

Answer 8

Species that move from one habitat to another during different times of the year.
- Migrate north in spring when there are short days and hot temperatures
- Migrate south in fall when there are short days and cold temperatures
- Allows species to stay in optimal conditions year-round

Ex: Mythmina Unipuncta
- Ideal temperature below 27 ºC
- Conditions have changed
- More days above 29 ºC in both summer and winter breeding grounds
- Pest → Rare species

Ex: Monarch Butterflies
- Different species prefer different milkweed species
- Overwintering: refers to how butterflies spend their winter months, migrated South
- Butterflies need to eat enough to survive during summer so that they do not need to rely on milkweed to survive at overwintering sites - flowers are food source in Texas
- In 2019 (year of early migration) - significant decrease in lipid content in Texas (due to heat) - caused to migrate early
- Lipid content always increases and reaches peak just before reaching overwintering site

Question 9

List examples of human influence on Anthropocene.

Answer 9

Deforestation of the Amazon Rainforest:
- Massive loss of habitat and oxygen producing species
- Disrupted ecosystems

Gold Mining
- Destruction of previous environment
- Significant water pollution
- Displacement of animals

There are many different factors that contribute to the anthropocene:
1) Fossil fuels (some countries rely on this as their source of energy - used by buildings, industries, transportation, electricity + heat, agriculture))
2) Agriculture (monoculture, habitat loss, loss of plants which take up CO2)
3) Mining (inc in pollution, mercury from illegal gold mining can leech into the water system)

Question 10

What are some factors contributing to the tipping point?

Answer 10

Present day greenhouse gases are higher than they’ve ever been, sea levels are rising, droughts are increasing.
1) Methane is a big concern, found in the permafrost, when temperature rises it is released into the air (methane traps more heat than CO2)
2) Temperature Relative Humidity
- Extended droughts can lead to the area becoming a desert
Drought conditions include:
- Decreased foraging
- Decreased flower availability
- Higher nectar viscosity
- Competition with resident nectivores
Even further decrease in lipid stores
- Increased precipitation can lead to increased amounts of floods
3) Decreased snow
- Loss of water source
- Also leads to over accessing the water from reserves in the ground which need to be used carefully
- Lack of snow also causes freezing of deeper and deeper soil which can harm plants and animals in the soil
4) Increased fires and decrease in glaciers

Question 11

Examples of international greed.

Answer 11

1% of the population contributes to the majority of the negative effects of the Anthropocene
- Celebrity private jet usage:
- Billionaires

Example:
African Agriculture Inc. in New York is growing alfalfa in the Ndiael desert nature preserve in Senegal
using water from Lake Guiers (the only water source for Dakar, a city of 3.5 mil with major water shortages)
Currently growing 300 hectares, want to increase to 20,000, which would be a disaster

Question 12

How can we fix this crisis?

Answer 12

What can we do as individuals?
Decrease use of plastic water bottles, change mode of transportation, explore different dietary restrictions, wear sustainable brands.

Individuals/local: bike instead of driving, avoid bottled water, try milk alternatives, turn the water off when you’re not using it, heat your house efficiently, be cognizant of what goes into manufacturing the things we use on a daily basis
Example: A single pair of jeans requires 5000-20000 L of water along it’s supply chain, including the water used for irrigating plants (virtual water)

International: renovate old buildings, zero deforestation, no new coal power plants, last fossil fuel car sold by 2035, zero emission buildings, best practice in agriculture, alternative food sources (insects)

As humans, we have the responsibility of the mitigation of climate change
Take action – make our cars, houses, buildings, and hospitals better and more sustainable!

Question 13

Difference between increasing and decreasing climate trends.

Answer 13

Increasing climate trends:
- Global surface temperature (land and ocean)
- Ocean heat content
- Carbon dioxide
- Sea level
- Methane
- Nitrous Oxide
- Specific humidity
- Middle tropospheric temperature

Decreasing climate trends
- Arctic and Antarctic sea ice extent
- Ocean pH
- Middle stratospheric temperature
- Global glacier mass balance
- Greenland ice sheet mass balance

Question 14

How does temperature affect sex determination in animals?

Answer 14

So, in a broad sense, if temperatures continue to fluctuate drastically, it can affect the distribution of males and females in the population. For certain species (like turtles), can depend on temperature:
<27.7°C : Male
>31°C : Female

Question 15

How do certain animals adapt to changing temperatures?

Answer 15

Example: The Univoltine
- Exposed to hot temperatures longer ∴ higher mortality
- Digs into the soil to cool down (over the winter until next spring)… but takes up energy.
- Over the month they enter the soil, temperatures can change drastically
- Amount of energy needed is soil and temperature dependent.
- Mortality increases if temperatures continue to increase
- Early cohort will enter the soil early → hot temperatures, more exposure, higher moratlity than the late cohort

Question 16

How does natural selection impact a population?

Answer 16

The way that natural selection will impact a population can depend on individual variability in thermal tolerance. You can have some species that have particularly high levels of temperature, but most will die at high temps. Most commonly, you will have a varied distribution of organisms that have different tolerances. So in this sense, population density can dictate how natural selection will impact the population.

Another example: the cucumber plant.
Increasing temperature, scientists found the plant to be:
- Smaller flower size
- Same bullseye area
- Bigger target
- Less nectar and pollen
Remember, there is a symbiotic relationship between a bee and the plant. Bee gains nectar, and helps the flower pollinate. Drought conditions changes the viscosity of the nectar making it difficult for bees to receive nectar, and as a result, pollination reduces. The symbiotic relationship between the bee and the flower is disrupted.

Question 17

What are some geographical changes?

Answer 17

Important to note that environmental changes causes many species to adapt geographically, this can be in 3 different ways:

Latitudinal:
Ex. Species’ geographic range can become more North over time

Altitudinal:
Ex. tropical birds are moving to higher altitudes as a result of climate change

Depth:
Ex. Distribution of species is changing according to sea levels

An example is the Pine Beetle from B.C.
- Warm winter → outbreak of the beetle
- Large acres of forest were damaged
- The beetle migrated over the Rockies → adapted to new tree species
- Rate of displacement is dependent on mobility → can vary for different animals

Question 18

Tropicalization

Answer 18

• Movement of organisms in response to warmer temperatures
• Generally causes increase in tropical species and decrease in temperate species
• Mangroves replacing salt marshes
• Think about food chains!
• Movement of organisms will disrupt the ecosystem - if there are predators better suited to the environment or who can outcompete for food
• Beneficial / decremental ?

Question 19

Overwintering

Answer 19

Refers to how butterflies spend their winter months, migrated south, they need to eat enough to survive during summer so that they don’t need to rely on milkweed to survive at overwintering sides.