Re-tell Lecture — Animal Behaviour

Read the lecture ONCE, then re-tell it in your own words in 40 seconds without looking back. Why birds migrate Every autumn, billions of birds fly thousands of kilometres from their breeding grounds to warmer regions, then return the following spring. The main driver is food availability: as temperatures drop, insects and seeds become scarce in northern latitudes. Birds that stay risk starvation, so migration is a survival strategy refined over millions of years. But the journey itself is dangerous. Predators, storms, and sheer exhaustion kill many along the way, and human structures such as tall buildings and power lines add further hazards. Researchers have found that birds navigate using the Earth's magnetic field, the position of the sun, and even visual landmarks remembered from previous trips. Interestingly, young birds on their first migration often follow experienced adults, but some species manage the journey entirely alone, guided purely by instinct encoded in their genes.

Read the lecture ONCE, then re-tell it in your own words in 40 seconds without looking back. How ants organise without a leader An ant colony can contain millions of individuals working together with remarkable efficiency, yet no single ant directs the operation. Instead, coordination emerges from simple rules that each ant follows independently. When a forager discovers food, it leaves a chemical trail of pheromones on the way back to the nest. Other ants detect this trail and follow it to the food source, reinforcing the scent signal as they return with their own loads. If the food source runs out, the trail gradually fades because no fresh pheromones are being deposited. This elegant feedback mechanism allows the colony to allocate workers dynamically: more ants travel to routes where food is plentiful, and fewer where it is not. The result is a highly adaptive system that responds quickly to changing environmental conditions without any central control, planning, or communication beyond simple chemical signals.

Read the lecture ONCE, then re-tell it in your own words in 40 seconds without looking back. Camouflage strategies in the animal kingdom Animals use camouflage in different ways depending on their environment and the threats they face. The simplest form is background matching, where an animal's colour or pattern blends with its surroundings. Arctic hares, for example, turn white in winter to match the snow. A more advanced strategy is disruptive colouration, in which bold patterns break up the animal's outline, making it harder for a predator to recognise its shape. Zebras are a classic example. Some species go even further. Cuttlefish can change both the colour and the texture of their skin within seconds, adapting to different backgrounds almost instantly. This ability is controlled by specialised cells called chromatophores, each of which can expand or contract to create new patterns.