A telltale trace was on the bee’s knees.
An evaluation of 127 fossil flowers, flower buds and bees from central Germany revealed pollen particles that exactly matched historic flowers to their pollinators. The fossils date to round 24 million years in the past. Whereas proof of earlier pollen-covered bugs exists, that is the oldest instance of a direct pollination relationship noticed between any two species, researchers report September 22 in New Phytologist.
“The mere presence of pollen adhered to the physique of a fossil bee solely confirms the insect made floral visits,” says Constanza Peña-Kairath, a specialist in historic insect pollination previously on the College of Barcelona who was not concerned within the examine. The brand new analysis gives “an important and exceptionally well-preserved piece of proof” of an unambiguous relationship between pollinator and the pollinated, she says.
Researchers collected the fossils from an historic crater lake in Enspel, which lies about halfway between Düsseldorf and Frankfurt. Thousands and thousands of years in the past, vegetation lined the lake and bees thrived alongside the shoreline. Often, bees and flowers would fall into the lake and get lined by sediments that may later fossilize their stays.
“Bugs fall into water our bodies and drown on a regular basis,” says Christian Geier, a paleobotanist on the College of Vienna. “Within the case of the fossilized bumblebees, they escaped being eaten by fish and ended up sinking all the way down to the underside of the lake.”
Geier and his colleagues recognized a brand new species of linden tree flower, Tilia magnasepala, and two new species of bumblebee, Bombus messegus and B. palaeocrater. These are the oldest recognized bumblebee fossils in Europe, Geier says.
Each the flowers and bees had been lined in pollen, which allowed the researchers to attempt to match the fossils like items of a puzzle.
Geier and his colleagues extracted pollen particles from a number of of the fossils and used a scanning electron microscope to look deep into the construction of the pollen. The pollen within the flowers matched the pollen on each new species of bees. Moreover, the bees had pollen on the undersides of their physique, together with their legs, mouthparts and abdomens, indicating they collected the pollen after they landed on the cupped-shaped linden flowers.
Proof of bugs carrying pollen of nonflowering vegetation goes again at the least 280 million years, lengthy earlier than an evolutionary burst of flowering vegetation round 130 million years in the past. The following widespread success of flowering vegetation — they now make up round 90 p.c of recent vegetation — is partly resulting from their pollinators, prior analysis has instructed.
At present, linden bushes nonetheless rely upon bumblebees for pollination, making this the longest recognized “direct proof for a bee-flower interplay that’s nonetheless ongoing in Europe,” says Friðgeir Grímsson, a paleobotanist additionally on the College of Vienna. Having the ability to hint a long-standing relationship between a plant and its pollinator again 24 million years “is what makes this so particular.”