The Physical Environment
Polar cell
Ferrel
cell
Ferrel cell
Hadley cell
Ferrel
cell
Image from NASA
Ferrel cell
The Ecological Niche
Joseph Grinnell
Grinnellian Niche  “Habitat”
“The niche relationships of the California Thrasher” (1917)
“The ultimate distributional unit within which each species is held by its
structural and instinctive limitations" (1928)
Photos of Grinnell and California Thrasher from Wikimedia Commons
The Ecological Niche
Charles Elton
Eltonian Niche  “Profession” or “Role”
“The status of an animal in its community… its place in the
biotic environment, its relations to food and enemies" (1927)
Photo of Elton from http://people.wku.edu/charles.smith/chronob/ELTO1900.htm
The Ecological Niche
Dr. Seuss
And NUH is the letter I use to spell Nutches
Who live in small caves, known as Niches, for hutches.
These Nutches have troubles, the biggest of which is
The fact there are many more Nutches than Niches.
Each Nutch in a Niche knows that some other Nutch
Would like to move into his Niche very much.
So each Nutch in a Niche has to watch that small Niche
Or Nutches who haven’t got Niches will snitch.
Image from Geisel, T. S. (1955) On beyond zebra, by Dr. Seuss
The Ecological Niche
G. Evelyn Hutchinson
Hutchinsonian Niche = “n-dimensional hypervolume”
“an n-dimensional hypervolume… defined on axes [representing]
all of the ecological factors relative to [the species]… [and] every point in which
corresponds to a state of the environment which [permits]…
the species… to exist indefinitely” (1958)
Photo of Hutchinson from http://peabody.yale.edu/collections/archives/biography/g-evelyn-hutchinson
Figure image from http://www.eplantscience.com/index/general_zoology/environment_and_the_niche.php
The Ecological Niche as a Metaphor
Let’s consider the concept of niche –
If I knew what it meant I’d be rich.
Its dimensions are n,
But a knowledge of Zen
Is required to fathom the bitch.
[Credited to Grant Cottam &
David Parkhurst in Hurlbert (1981)]
Image from https://themerelyreal.wordpress.com/tag/words/
The Ecological Niche as a Metaphor
With your concept of niche I agree
But there’s clearly one hitch I can see.
You blame the wrong sex
For the inherent hex,
For the niche is no she, but a he.
[Credited to Joy Zedler in Hurlbert (1981)]
Image from https://themerelyreal.wordpress.com/tag/words/
The Ecological Niche as a Metaphor
I’m amazed that a smart woman like Joy
Would believe that a niche is a boy;
For a niche is elusive,
Deceitful, confusive –
It’s quite clear it’s a feminine ploy.
[Credited to Grant Cottam in Hurlbert (1981)]
Image from https://themerelyreal.wordpress.com/tag/words/
The Ecological Niche
Why might the
fundamental and
realized niches differ?
Figure from Bruno et al. (2003) Trends in Ecology & Evolution
Weather
Atmospheric environmental conditions at a given time and place
Photo of lightning in Western Australia from Wikimedia Commons
Climate
The long-term, average weather patterns of a given place
Climate Diagram from Cain, Bowman & Hacker (2014), Ecological Toolkit 3.1, Fig. A
Major Determinants of Global Climate
1. Shape of the Earth – differential heating & cooling
Major Determinants of Global Climate
1. Shape of the Earth – differential heating & cooling results
in rising & sinking air masses: Hadley & Ferrel cells
Polar cell
Ferrel
cell
Ferrel cell
Hadley cell
Ferrel
cell
Figure from NASA
Ferrel cell
Major Determinants of Global Climate
1. Shape of the Earth
2. Revolution of the Earth around the Sun on a tilted axis
– results in seasons as Hadley & Ferrel cells move latitudinally, tracking
changes in the position of the solar equator with a slight time lag
Northern
Hemisphere
summer –
Northern
Hemisphere
is tilted towards
the Sun
Figure from Wikimedia Commons
Northern
Hemisphere
winter –
Southern
Hemisphere
is tilted towards
the Sun
Major Determinants of Global Climate
1. Shape of the Earth
2. Revolution of the Earth around the Sun on a tilted axis
Major Determinants of Global Climate
1. Shape of the Earth
2. Revolution of the Earth around the Sun on a tilted axis
Major Determinants of Global Climate
1. Shape of the Earth
2. Revolution of the Earth around the Sun on a tilted axis
3. Rotation of Earth on Earth’s axis
Creates Coriolis effect (actually conservation of momentum)
Currents in air and water are deflected right in
N. Hemisphere and left in S. Hemisphere
Major Determinants of Global Climate
1. Shape of the Earth
2. Revolution of the Earth around the Sun on a tilted axis
3. Rotation of Earth on Earth’s axis
Creates Coriolis effect (actually conservation of momentum)
Currents in air and water are deflected right in
N. Hemisphere and left in S. Hemisphere
Figure from NASA
Local-Scale Influences on Climate
Albedo – solar radiation that a surface reflects
Sensible heat loss – exchange of kinetic energy via
conduction (molecules in direct contact) or
convection (air movement) that involves a temperature change
Latent heat loss – involves no change in temperature, e.g., phase shift of H2O
Cain, Bowman & Hacker (2014), Fig. 2.19
Local-Scale Influences on Climate
Rainshadow
Cain, Bowman & Hacker (2014), Fig. 2.18
Ocean Currents are Driven by Surface Winds
… and modified by Coriolis effects
Cain, Bowman & Hacker (2014), Fig. 2.11
Local-Scale Influences on Marine Conditions
Upwelling – brings cold, nutrient-rich water to the surface
Upwelling animation from Wikimedia Commons
Marine Biological Zones
Increasing pressure
Decreasing temperature
Decreasing light
availability
Cain, Bowman & Hacker (2014), Fig. 3.16
Rivers & Lotic Zonation
Stream order influences energy, nutrients, and other conditions
Temperate zone river
systems
Decrease in particle size
in stream bed
Allochthonous input of
detritus decreases relative
to volume of water
Cain, Bowman & Hacker (2014), Fig. 3.13
Rivers & Lotic Zonation
Location within a given section also determines conditions
Cain, Bowman & Hacker (2014), 3.14
Lakes & Lentic Zonation
Lake stratification & turnover
Increasing pressure
Decreasing temperature
Decreasing light
availability
Cain, Bowman & Hacker (2014), Fig. 2.22
Year-to-Year and Decadal
Climate Variation
E.g., El Niño Southern Oscillation
Normal yr
El Niño yr
Images from Wikimedia Commons
La Niña yr
Long-Term Climate Variation
Milankovitch Cycles
Orbital
Eccentricity
Periodicity 
100,000 yr
Orbital
Obliquity
Periodicity 
41,000 yr
Cain, Bowman & Hacker (2014), Fig. 2.26 A & B
Long-Term Climate Variation
Milankovitch Cycles
Orbital
orientation
Periodicity 
22,000 yr
Cain, Bowman & Hacker (2014), Fig. 2.26 C
Chemical Environment
pH
E.g., development – sea urchin development suffers under
elevated pH (resulting from elevated pCO2)
pH level
p < 0.001
Kelly et al. (2013) Global Change Biology, Fig. 4
Chemical Environment
Oxygen
(Increasing)
Hb-O2 affinity
E.g., biochemical phenotype – hemoglobin’s O2 binding affinity increases
with the average elevation range of Andean hummingbird species
Elevation
Projecto-Garcia et al. (2013) Proceedings of the National Academy of Sciences, Fig. 1b.
Chemical Environment
Salinity / Salt Availability
E.g., behavior – frugivorous bats seek sodium at
mineral licks in southeastern Peru
Dry season
Wet season
Season
p = 0.48
Site
p < 0.001
Season x Site
Interaction
p = 0.62
Bravo et al. (2010) Journal of Tropical Ecology, Fig. 1