Reading so that their seeds are not chewed, Ochradenus baccatus so-called glycosinolates in them, which are extremely spicy. However, spiked mice can not be stopped from eating the plant's sweet berries? they simply spit out the seeds again, for the benefit of Ochradenus baccatus. On the menu of the Egyptian spiny mouse Acomys cahirinus are, among others, the berries of the cruciferous Ochradenus baccatus. However, the rodents do not eat the whole fruit, but spit out the seeds again (see video). "The animals prevent the seeds from becoming toxic, " explains Denise Dearing of the University of Utah at Salt Lake City. Together with Israeli scientists, the biologist has examined the fight between the mice and the plant in more detail.
Both the rodents and Ochradenus baccatus are adapted to (semi-) arid areas. The mice, which are native to Arabia and the Near East, do not have too many food sources and places for shelter. It is all the more important for the plants there to protect themselves from the predators. Ochradenus baccatus is similar to chili plants: roots, leaves, stems and berries of the plant, which is about 1.5 meters high, contain glycosinolates, GLS for short. In conjunction with the enzyme myrosinase, the substance has a toxic effect. If mice eat the berries and bite up to 20 seeds, the GLS and myrosinase come from the pulp, and the little rodents get the "mustard oil bomb". to feel the plant. The result: you lose a lot of weight. The plant can only be eaten by certain mice? namely those that do not bite the seeds but spit them out again, explains Dearing. That's exactly what the spiked mice do. Mouse and plant enter into a kind of symbiosis: The mouse can eat the sweet and water-rich berries? and the seeds of the plant remain intact.
Ochradenus baccatus. Clever Mice
For Ochradenus baccatus the spiny mice are a welcome guest for another reason: They usually do not eat the berries directly under the plant, but rather in a place protected from the sun ? optimal conditions for the seeds to germinate. However, the plant can not rely on it. "Some mice came back after a few hours and then ate the seeds, " reports Denise Dearing. For when the porridge containing myrosinase has completely disappeared from the mouth of the mice, the cores can no longer harm them.Michael Samuni-Blank (University of Utah, Salt Lake City): Current Biology, doi: 10.1016 / j.cub.2012.04.051 © science.de? Marion Martin