Adaptations to the Physical Environment: Water and Nutrients A. Properties and Adaptations 1. High Specific Heat Property: Takes a large change in E to change temp and state… so water is a stable internal and external environment

Adaptations to the Physical Environment: Water and Nutrients A. Properties and Adaptations 1. High Specific Heat Property: Takes a large change in E to change temp and state… so water is a stable internal and external environment, and evaporation cools surfaces

Adaptations to the Physical Environment: Water and Nutrients A. Properties and Adaptations 1. High Specific Heat 2. Density and Viscosity ocean “fresh”

Adaptations to the Physical Environment: Water and Nutrients A. Properties and Adaptations 1. High Specific Heat 2. Density and Viscosity Positively Affect Buoyancy Gases (swim bladder) Low Density Fluids Fats, Oils Bone, Cartilage Shell Chitinous Exoskeleton Heavy Ions “Buoyancy” is a function of relative density of the organism to its environment. Negatively Affect Buoyancy

Adaptations to the Physical Environment: Water and Nutrients A. Properties and Adaptations 1. High Specific Heat 2. Density and Viscosity Viscosity of Water Temperature [°C] Viscosity [mPa·s] 10 1.308 20 1.002 30 0.7978 40 0.6531 50 0.5471 60 0.4658 70 0.4044 80 0.3550 90 0.3150 100 0.2822 Hydrodynamic shape is adaptive in mobile organisms Small organisms may exploit viscosity and drag to slow sinking rate

Adaptations to the Physical Environment: Water and Nutrients A. Properties and Adaptations 1. High Specific Heat 2. Density and Viscosity 3. Universal Solvent Ions and polar compounds dissolve in water, and become available for uptake or for chemical reactions. - H2O + CO2  H2CO3 (carbonic acid) - H2CO3 (carbonic acid)  H+ + HCO3- (bicarbonate) - HCO3- (bicarbonate)  2H+ + CO32- (carbonate) Ca2+ is at maximum solubility in oceans, so it precipitates out with the carbonate as CaCO3

Adaptations to the Physical Environment: Water and Nutrients A. Properties and Adaptations 1. High Specific Heat 2. Density and Viscosity 3. Universal Solvent 4. Water Dissociates Feldspar minerals: KAlSi3O8 - NaAlSi3O8 - CaAl2Si2O8 (60% of the Earth’s crust) Freeing H+ is solution, which can displace other cations bound minerals; this is chemical weathering, and it makes these cations available for bio-uptake (K+, Al+, Na+, Ca+)

Adaptations to the Physical Environment: Water and Nutrients A. Properties and Adaptations 1. High Specific Heat 2. Density and Viscosity 3. Universal Solvent 4. Water Dissociates 5. Water is Adhesive and Cohesive

[1] Adaptations to the Physical Environment: Water and Nutrients A. Properties and Adaptations 1. High Specific Heat 2. Density and Viscosity 3. Universal Solvent 4. Water Dissociates 5. Water is Adhesive and Cohesive 6. Water Potential - mechanical pressure (+) - gravitational pressure (+) - humidity pressure (+) - solute/osmotic pressure (-) - matrix adhesion effects (-)

Adaptations to the Physical Environment: Water and Nutrients A. Properties and Adaptations 1. High Specific Heat 2. Density and Viscosity 3. Universal Solvent 4. Water Dissociates 5. Water is Adhesive and Cohesive 6. Water Potential 7. Plants

Adaptations to the Physical Environment: Water and Nutrients A. Properties and Adaptations 7. Plants Water uptake by roots Plant use a H+ pump to actively transport H+ out of cell; this causes cation displacement of cations, that either diffuse into the cell or are actively transported into the cell… Increase solute concentration decreases water potential in cell Water moves in by osmosis

Adaptations to the Physical Environment: Water and Nutrients A. Properties and Adaptations 7. Plants Water uptake by roots Water is transported between root cells through plasmodesmata – cytoplasmic connection through cell walls.

Adaptations to the Physical Environment: Water and Nutrients A. Properties and Adaptations 7. Plants Water uptake by roots Cl- ions are actively transported from endodermal cells (pericycle), and water follows into the xylem by osmosis.

Adaptations to the Physical Environment: Water and Nutrients A. Properties and Adaptations 7. Plants Transport in xylem Facilitated by capillary action – the combined effects of cohesive and adhesive forces in small tube

Adaptations to the Physical Environment: Water and Nutrients A. Properties and Adaptations 7. Plants Action in the leaf a – water flows into cells and vaporizes in spongy mesophyll b – vapor moves from substomal air space (b) out of leaf (c), drawing more water into substomatal space from xylem c- under dry conditions, guard cells shrivel, closing the stoma, reducing evaporative water loss

Adaptations to the Physical Environment: Water and Nutrients A. Properties and Adaptations 8. Animals

Adaptations to the Physical Environment  II. Light A. Properties and Adaptations 1. Pigment Absorbances

Adaptations to the Physical Environment  II. Light A. Properties and Adaptations 1. Pigment Absorbances

Adaptations to the Physical Environment  II. Light A. Properties and Adaptations 2. C3 Photosynthesis

Adaptations to the Physical Environment II. Light A. Properties and Adaptations 2. C3 Photosynthesis THE LIGHT REACTION e- acceptor NADP NADPH e- ATP ADP+P PS I e- Water is split to harvest electrons; oxygen gas is released as a waste product. PS II 2H2O 4e + 4H+ + 2O (O2)

Light Dependent Reaction Light Independent Reaction The Light Dependent Reaction e- C6 (glucose) ATP ADP+P 6 CO2 e- Light Dependent Reaction Light Independent Reaction

Light Dependent Reaction Light Independent Reaction The Light Dependent Reaction The Light Independent Reaction e- C6 (glucose) ATP ADP+P 6 CO2 e- Light Dependent Reaction Light Independent Reaction

CO2 The Light Independent Reaction C6 C5 RuBP 2 C3 (PGA) A molecule of CO2 binds to Ribulose biphosphate, making a 6-carbon molecule. This molecule is unstable, and splits into 2 3-carbon molecules of phosphoglycerate (PGA)

6CO2 III. The Light Independent Reaction 6C6 6C5 RuBP 12 C3 (PGA) Now, it is easier to understand these reactions if we watch the simultaneous reactions involving 6 CO2 molecules

Adaptations to the Physical Environment  II. Light A. Properties and Adaptations 2. C3 Photosynthesis THE LIGHT INDEPENDENT REACTION 6CO2 6C6 6C5 RuBP 12 C3 ATP ADP+P 10 C3 2 C3 C6 (Glucose) NADPH NADP 2 of the 12 PGA are used to make glucose, using energy from ATP and the reduction potential of NADPH… essentially, the H is transferred to the PGA, making carbohydrate from carbon dioxide.

6CO2 6C6 6C5 12 C3 10 C3 2 C3 The Light Independent Reaction C6 RuBP 12 C3 ATP ADP+P ATP ADP+P 10 C3 2 C3 C6 (Glucose) NADPH NADP More energy is used to rearrange the 10 C3 molecules (30 carbons) into 6 C5 molecules (30 carbons); regenerating the 6 RuBP.

Review: Need water (from the xylem) And CO2 (through the stoma). Water vapor and waste O2 Are released (through stoma) Sugars are shunted into the phloem, Next to the xylem in vascular bundles, and distributed to the rest of the plant.

Problem: If the rate of water loss through the stoma (determined by relative humidity and temperature of air, relative to leaf) IS GREATER THAN The rate of water absorption (dependent on amount of water and soil characteristics determining water availability) THE LEAF DRIES AND STOMATES CLOSE

Problem: If the rate of water loss through the stoma (determined by relative humidity and temperature of air, relative to leaf) IS GREATER THAN The rate of water absorption (dependent on amount of water and soil characteristics determining water availability) THE LEAF DRIES AND STOMATES CLOSE Water vapor is retained, but: - as photosynthesis continues, [CO2] declines and [O2] increases inside the closed leaf. - When [CO2] is low, RuBP won’t bind it anymore and photosynthesis stops. Indeed, RuBP is broken down (photorespiration). - In hot, dry habitats, stomates close early in the day and C3 plants can’t make enough glucose to survive.

Adaptations to the Physical Environment  II. Light A. Properties and Adaptations 2. C3 Photosynthesis 3. C4 Photosynthesis Many plants that live in dry habitats have a modified carbon fixation pathway Grasses, including important crops like cane and maize

Adaptations to the Physical Environment  II. Light A. Properties and Adaptations 2. C3 Photosynthesis 3. C4 Photosynthesis Leaf Anatomy of a C4 Plant Note that the Bundle Sheath cells ARE surrounded by another layer of tissue – photosynthetic mesophyll

C4 - Spatial Separation Carbon fixation, by PEP occurs in the mesophyll. PEP can bind CO2 even at low CO2 concentrations.

C4 - Spatial Separation Carbon fixation, by PEP occurs in the mesophyll. PEP can bind CO2 even at low CO2 concentrations. The product, a C4 malate, is transferred to the bundle sheath and dissociates, recycling the PEP and releasing the CO2

C4 - Spatial Separation Carbon fixation, by PEP occurs in the mesophyll. PEP can bind CO2 even at low CO2 concentrations. The product, a C4 malate, is transferred to the bundle sheath and dissociates, recycling the PEP and releasing the CO2 So, CO2 is pumped into the BSC, keeping concentrations high enough for RUBP to bind CO2 in the Calvin Cycle and produce glucose, even when CO2 concentrations are low in the leaf because the stomates are closed.

Whereas C3 plants shut down at high light intensity and temp, C4 continue to photosynthesize

Temporal Separation of Carbon Fixation and Calvin Cycle Adaptations to the Physical Environment  II. Light A. Properties and Adaptations 2. C3 Photosynthesis 3. C4 Photosynthesis 4. CAM Photosynthesis Temporal Separation of Carbon Fixation and Calvin Cycle

Radiation – E emitted from a surface Conduction – kinetic E trans. By contact Convection – moving air/liquid (boundary) Evaporation – exchange of latent E Adaptations to the Physical Environment  II. Light III. Heat Exchange A. Pathways of Exchange

Adaptations to the Physical Environment II. Light III. Heat Exchange Pathways of Exchange Effects on Organisms 1. Heat Budget

Adaptations to the Physical Environment II. Light III. Heat Exchange Pathways of Exchange Effects on Organisms 1. Heat Budget 2. Body Size and SA/V ratio

Bergman’s Rule White-tailed Deer Bears

humans

Adaptations to the Physical Environment II. Light III. Heat Exchange Pathways of Exchange Effects on Organisms 1. Heat Budget 2. Body Size and SA/V Ratio 3. Effects of Temperature Increase metabolism, increase production of metabolic waste Increase evaporation Increase water demand

Adaptations to the Physical Environment  II. Light III. Heat Exchange Pathways of Exchange Effects on Organisms Adaptations Concept of flux: The rate of exchange of energy or matter (water) is a function of: - SA/V - energy/matter concentration gradient - characteristics of the surface (covered by oils or hairs?) Cushion plants Cacti

Adaptations to the Physical Environment II. Light III. Heat Exchange Pathways of Exchange Effects on Organisms Adaptations 1. Structural Reduce limb length as latitude increases Allen’s Rule

increase edge/SA ratios, and increase SA/V ratios - maximize the loss of absorbed heat energy   shade leaf - broad sun leaf - deeply cut; narrow

Adaptations to the Physical Environment II. Light III. Heat Exchange Pathways of Exchange Effects on Organisms Adaptations 1. Structural Hairs, spines, feathers… create boundary layer.

Adaptations to the Physical Environment II. Light III. Heat Exchange Pathways of Exchange Effects on Organisms Adaptations 1. Structural 2. Physiological

Adaptations to the Physical Environment II. Light III. Heat Exchange Pathways of Exchange Effects on Organisms Adaptations 1. Structural 2. Physiological

Adaptations to the Physical Environment II. Light III. Heat Exchange Pathways of Exchange Effects on Organisms Adaptations 1. Structural 2. Physiological

Adaptations to the Physical Environment II. Light III. Heat Exchange Pathways of Exchange Effects on Organisms Adaptations 1. Structural 2. Physiological

Adaptations to the Physical Environment II. Light III. Heat Exchange Pathways of Exchange Effects on Organisms Adaptations 1. Structural 2. Physiological

Adaptations to the Physical Environment II. Light III. Heat Exchange Pathways of Exchange Effects on Organisms Adaptations 1. Structural 2. Physiological

Adaptations to the Physical Environment II. Light III. Heat Exchange Pathways of Exchange Effects on Organisms Adaptations 1. Structural 2. Physiological 3. Behavioral

Adaptations to the Physical Environment II. Light III. Heat Exchange Pathways of Exchange Effects on Organisms Adaptations 1. Structural 2. Physiological 3. Behavioral

IV. Life History Evolution Trade-Offs Components of fitness? - probability of survival - number of offspring - probability that offspring survive

IV. Life History Evolution Trade-Offs 2. Relationships with Energy Budgets METABOLISM GROWTH SURVIVAL METABOLISM REPRODUCTION REPRODUCTION

IV. Life History Evolution Trade-Offs 3. Trade-offs Between Survival and Reproduction Maximize probability of survival Maximize reproduction GROWTH METABOLISM GROWTH REPRODUCTION METABOLISM REPRODUCTION

IV. Life History Evolution Trade-Offs 3. Trade-offs Between Survival and Reproduction European Kestrels

IV. Life History Evolution Trade-Offs 3. Trade-offs Between Survival and Reproduction Cox, R.M., and R. Calsbeek. 2010. Severe costs of reproduction persist in Anolis lizards despite the evolution of a single-egg clutch. Evolution 64: 1321-1330.

IV. Life History Evolution Trade-Offs 3. Trade-offs Between Survival and Reproduction

IV. Life History Evolution Trade-Offs 3. Trade-offs Between Survival and Reproduction - Suppose the probability of adult survival is low for other reasons? Can wait Can’t wait

Selection favors high fecundity in “fish” living less than four years, but low fecundity for fish living more than four years

IV. Life History Evolution Trade-Offs 3. Trade-offs Between Survival and Reproduction - Suppose the probability of adult survival is low for other reasons? Can vary within a species in different environments: Guppies

IV. Life History Evolution Trade-Offs 4. Trade-offs Between # offspring and offspring survival METABOLISM REPRODUCTION REPRODUCTION METABOLISM A few large, high prob of survival Lots of small, low prob of survival

IV. Life History Evolution Trade-Offs 4. Trade-offs Between # offspring and offspring survival – Lack Hypothesis Again, diminishing returns

IV. Life History Evolution Trade-Offs 4. Trade-offs Between # offspring and offspring survival – Lack Hypothesis Varies within a species under different environmental conditions: Guppies

IV. Life History Evolution Trade-Offs Timing 1. First Age of Reproduction As lifespan increases, selection favors a delayed first age or reproduction

III. Population Growth – change in size through time Calculating Growth Rates B. Life History Redux - increase fecundity, increase growth rate (obvious) x lx bx lxbx xlxbx 1.0 1 0.5 20 10 2 - R = 10 T = 1 r = 2.303 x lx bx lxbx xlxbx 1.0 1 0.5 22 11 2 - R = 11 T = 1 r = 2.398

III. Population Growth – change in size through time Calculating Growth Rates B. Life History Redux - increase fecundity, increase growth rate (obvious) - decrease generation time (reproduce earlier) – increase growth rate x lx bx lxbx xlxbx 1.0 1 0.5 22 11 2 - R =11 T = 1 r = 2.398 x lx bx lxbx xlxbx 1.0 2 1 0.5 20 10 - R = 12 T = 0.833 r = 2.983

III. Population Growth – change in size through time Calculating Growth Rates B. Life History Redux - increase fecundity, increase growth rate (obvious) - decrease generation time (reproduce earlier) – increase growth rate - increasing survivorship – DECREASE GROWTH RATE (lengthen T) x lx bx lxbx xlxbx 1.0 1 0.5 22 11 2 - R = 11 T = 1 r = 2.398 x lx bx lxbx xlxbx 1.0 1 0.5 20 10 2 3 - R = 20 T = 1.5 r = 2.00

III. Population Growth – change in size through time Calculating Growth Rates B. Life History Redux - increase fecundity, increase growth rate (obvious) - decrease generation time (reproduce earlier) – increase growth rate - increasing survivorship – DECREASE GROWTH RATE (lengthen T) - survivorship adaptive IF: - necessary to reproduce at all - by storing E, reproduce disproportionately in the future x lx bx lxbx xlxbx 1.0  0 1 0.9 2 0.8 200 160 320 3 0.7 100 70 210 4 - R = 230 T = 2.30 r = 2.36 Original r = 2.303

IV. Life History Evolution Trade-Offs Timing 1. First Age of Reproduction 2. Parity: How Often to Reproduce - Semelparous vs. iteroparous Semelparity = once Iteroparity = iterative… many

IV. Life History Evolution Trade-Offs Timing 1. First Age of Reproduction 2. Parity: How Often to Reproduce - Semelparous vs. iteroparous

III. Life History Evolution Trade-Offs Timing 1. First Age of Reproduction 2. Parity: How Often to Reproduce 3. Senescence Why do human have a long post-reproductive period? The ‘grandmother effect’ Lahdenpera et al., 2005. Nature.

III. Life History Evolution Trade-Offs Timing Life History Strategies