BIOL 1902 Lecture Notes - Rumen, Depth Perception, Parasitism
Document Summary
Plants also have chemical defences to overcome: some herbivores sequester the toxins. Vein drain strategy to prevent digesting toxins: some use enzymes to counter toxins (mixed function oxidases mfos) Neutralizes plant toxins inside body: some herbivores are specialists, eating only one or two kinds of food. Red-headed pine sawflies eat pine needles: others are generalists (do not need to know what they eat, some animals switch foods for a balanced diet. Fresh leaves and twigs = high carbohydrates, protein, low sodium. Advantages: can be hard to find. Some animals eat dead animals: parasitism, scavenging. Keen eyesight large number of cones. Large eyes more light: glycogen rich rods = sensitive vision, frontal placement = more depth perception. Tiger beetles hunt visually and have large compound eyes. Dragonflies are visual hunters: eye can have 28,000 eyes ommatidia (6 or 7 sensory cells each) Whirligig beetles can see above and below the water at the same time.