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Pollination is the transfer of pollen from anther to stigma, which allows fertilisation and seed formation. Animal-pollinated plants reward visitors with nectar and pollen; bees and flowering plants have co-evolved for over 100 million years.

A honeybee colony is divided into castes: one reproductive queen, non-reproductive female workers whose tasks change with age, and male drones. Workers keep the brood at about 34 °C. When a colony swarms, the queen leaves with up to two thirds of the workers; a swarm holds about 10,000 workers.

To make honey, hive bees use enzymes to break sucrose in nectar into simpler sugars, then fan the stored liquid until the water content falls from 50–70% to about 18–20%. One pound (about 0.45 kg) of honey takes visits to about 2 million flowers.

Experiment: Decoding the waggle dance

1. Plot the calibration data: waggle-run time (s) on the x-axis against distance (m) on the y-axis: 0.5 s → 200 m, 1.0 s → 800 m, 1.5 s → 1,400 m, 2.0 s → 2,000 m, 3.0 s → 3,200 m.
2. Draw the line of best fit and find its gradient and intercept. Write the equation in the form d = m·t + c.
3. In pairs, one student is the 'scout'. Using a card, they walk a straight waggle run on a vertical wall chart (or on the floor, with 'up' taped as the direction of the sun) at the card's angle, for a time chosen from the graph.
4. The 'recruits' time each waggle run with a stopwatch and measure its angle with the protractor. Repeat for 6 runs and take the mean.
5. Use your equation to convert the mean time into a distance, and the angle into a direction relative to the sun.
6. Compare with the card. Work out the percentage error and discuss its sources.

Run	Time (s)	Angle from 'up' (°)
1
2
3
4
5
6
Mean
Distance from equation (m)

Questions

1. Explain how a honeybee colony divides its work between queen, workers and drones.

2. From your graph, give the equation of the line and use it to find the distance for a 1.2 s run.

3. Calculate the mass of honey (20% water) made from 2.0 kg of nectar with 70% water. Show your working.

4. Give two sources of uncertainty in your waggle-dance timings and explain how you reduced them.

Sources for every fact on this sheet: echoesof.science/school/bees/sources/

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