BIOL3045 Lecture Notes - Lecture 21: Response Surface Methodology
3 Jul 2018
School
Department
Course
Professor
Animal Ecological Physiology BIOL3045 460381099
Lecture 21: Nutritional ecology.
Amounts based nutritional geometry LAB: Utilisation and consequences.
Regulation of excretion
• Generalist Locusts - Plotting protein excreted vs protein eaten and marking where the intake
target is along the x axis shows that when in excess protein, locusts can excrete 100% of the
excess they consume to help rebalance their nutrients. Also able to down regulate excretion
when protein eaten is deficit.
• Specialists can’t do this, as they will be poisoned. This explains why generalists can over eat such
protein intakes.
Regulation of body composition
• Locusts - Plotting fat stores against differing P:C diets and marking where the intake target
belongs for both generalists and specialists shows that:
o Excess carbs: Increase body fat in both generalists and specialists.
o Excess proteins: Generalists regulate body fat by utilising protein as an energy source
(Gyconeogenesis). Specialists decrease body fat because they aren't able to use protein
as an energy source so rely on carbohydrates to drive energy metabolism and therefore
when deficit in carbs they lose weight.
Consequences of diet choice
• Plot egg production in predatory beetle, and use response surface. When given any nutritional
ratio they want, they eat towards target and get to maximum egg production.
