The fruits of the cycad Macrozamia, are known to be highly toxic for consumption.

Which of the following methods conducted by Indigenous peoples is most effective in removing toxins from this cycad?

1. Letting the seeds mature before consuming them.
2. Removing the individual seeds from the fruit before cooking them in a fire.
3. Cooking the seeds with fire before leaching them out in running water overnight.
4. Removing the individual seeds from the fruit and baking them in the sun.

For centuries, Indigenous Australians have used chemical processes to detoxify certain foods. The seeds of the nardoo fern (Marsilea) were a traditional food source, but they contain harmful toxins. To safely consume the seeds, they were first ground into a paste and soaked in water for several days.

Soaking the nardoo seeds aids in detoxification by:

1. Causing the water to neutralise the harmful substances.
2. Altering the chemical structure of the toxins through grinding.
3. Allowing the water to remove the toxins from the paste.
4. Increasing the temperature to speed up the breakdown of toxins.