Australian mice favor nectar over cheese: researchers have found these rodents pollinating flowers.

For a long time, it was believed that shrubs and trees with vibrant flowers, such as banksias, were primarily pollinated by birds and marsupials, which were rewarded with a substantial amount of nectar. However, a research team from La Trobe University in Australia has discovered that the local ash-colored mouse (Pseudomys albocinereus) plays a significant role in the pollination of certain species of these plants. These small mammals, which are among the rare placental (rather than marsupial) species that colonized Australia long before humans, have shown a fondness for indulging in nectar.

2024-10-26 07:30:03https://naked-science.ru/article/biology/avstralijskie-myshi-predp

Although a significant portion of Australia consists of arid or semi-arid regions, the southwest of the country features a Mediterranean climate and rich biodiversity, home to both tree and shrub banksias. However, several species of these plants, with flowers situated very close to the ground or just above it, can be found in the heathlands of Western Australia.

A study whose results were published in the journal Botanical Journal of the Linnean Society presents four species of banksias: Banksia shuttleworthiana and Banksia subulata, which have a strong musky fragrance and flowers located near the ground (suggesting their adaptation to pollination by animals that rely on scent for foraging), and Banksia sessilis and Banksia splendida, featuring bright, scentless flowers.

The team discovered an unexpected nectar lover—the local ash-gray mouse—by observing flower visitation by various pollinators using motion-sensor cameras. The experiment took place on the sandy plain of Lesueur near Jurien Bay in Western Australia, where diverse species of banksias are present.

The results indicated that banksias with fragrant flowers located close to the ground attracted more mammals, including the honey possum (Tarsipes rostratus), ash-gray mouse, and house mouse (Mus musculus). The involvement of the latter in the pollination of Banksia subulata was surprising yet significant, as it suggests a potential role in this process for both native and invasive rodent species. Meanwhile, the bright flowers of the other two scentless plant species were more frequently visited by honeyeaters (Meliphagidae), known for their pollination abilities.

Pollination by rodents is not a new concept. The fact is that the pollen and nectar of most flowering plants attract various animals, including mammals, bats, and small reptiles. However, the primary role of ash-gray mice as pollinators of Banksia subulata, sipping nectar from the flowers (rather than marsupials, as researchers had assumed), has been identified for the first time.

Thus, the team obtained the first compelling evidence of primary rodent pollination in Australia. The study's results also indicated that the traditional classification of pollinators by plant type may be overly simplistic and warrants reconsideration. It is likely that both birds and mammals, including rodents, play an important role in plant pollination, depending on the species.

“While many banksias have evolved to rely on pollinators such as birds and mammals, there may be other unexpected pollination strategies yet to be discovered,” the authors of the study concluded.