Text and photo: Rubén Torices
To mark World Evolution Day, celebrated today, November 24th, we want to share a very interesting post with you:
Anacyclus clavatus is a Mediterranean plant known for having two types of fruit: winged and wingless. The function of these wings has always been assumed to be what one would expect in any winged fruit: to allow the fruit to extend its flight time and thus achieve greater dispersal distances. So far, nothing unusual for daisies… But the surprise came when researchers discovered that these wings, instead of increasing flight distances, accelerate germination: the winged fruits absorb water faster, carry it directly to the seed, and trigger the start of growth sooner. They are able to germinate in less than 24 hours and always win the race against their wingless counterparts.
Because in semi-arid ecosystems, rapid germination can mean the difference between life and death: if the rain stops, whoever sprouts first survives. And in this humble plant, evolution has taken this to heart. The winged fruits are only released from the plant when it rains. The first autumn rains cause the structures that hold the fruits to open, allowing the fruits to fall to the ground precisely when there is water, neither before nor after.
Interestingly, the fruits without wings remain on the plant longer and are only released weeks later. Their combined function with the winged fruits is attributed to an evolutionary bet-hedging strategy to ensure that if the first rains have not been sufficiently abundant, the new seedlings born from the wingless fruits serve as a reserve against potential mortality among the first ones to arrive (Torices et al., 2024).
The next time you take a walk in spring and are lucky enough to come across hundreds of flowers of this common plant that loves our roadsides, don’t quickly dismiss it for inhabiting such unrefined environments and remember that you have before your eyes an evolutionary marvel of nature.