Attracting pollinators is a key action in reproduction for many plants. If there aren’t suitable pollinators available at a location, then it’s difficult to maintain a population. Some plants are happy to attract generalist pollinators and risk losing pollen to incompatible partners. Some plants take a different tack. They attract specialist pollinators. By encouraging a pollinator to favour one specific species, they ensure their pollen is delivered to another plant that can use it.

Eucomis regia, the pineapple lily, is an odd plant. It has open flowers, so its nectar is available to whatever chooses to visit. Insects and birds don’t visit. This doesn’t seem to bother the pineapple lily, which doesn’t seem interested in attracting them. Its flowers are green, giving the impression that the plant would rather not attract visitors. And the scent is odd.

Petra Wester and colleagues, who have studied E. regia, describe the smell as like boiled potatoes. It’s unusual and got the botanists thinking. Is the reason the plant looks like it’s not attracting visitors is because it really isn’t, and using scent instead of flower shape to attract specialist pollinators? The smell of the flower is due to some sulphur compounds. Wester and her co-authors knew that this was used by some plants to attract plants, but the pineapple lily flowers are close to the ground. Could some other mammal be pollinating the plant? The team set out to find what was going on.

To find if mammal pollination is going on, the team set out to examine multiple questions.
* What is visiting the flowers?
The scent hints at mammal visitors, but are other insects attracted to the smell?
* If mammals are visiting, are they transferring pollen, or are they just getting a free meal of nectar from the plant?
If the visitors aren’t actually transferring pollen, it could be they’ve learned to identify the scent with food, but the plant isn’t in a position to use them as carriers.
* Do the plants need these visits?
Is the pollen the visitors transfer significant, or are the plants self-pollinating and the transfer isn’t contributing much to the plant’s reproduction.

Wester and colleagues set up cameras around some E. regia plants. They found that the cameras didn’t see any insect of bird visitors, even though other nearby plants attracted them as pollinators. What they did find at the plants were small mammals. Micaelamys namaquensis is the Namaqua Rock Mouse. It would lap at the flower’s nectar and get dusted with pollen as it did so. The mice were not perfect pollinators for the plant, as sometimes they’d groom themselves to remove pollen.