16-Million-Year-Old Dominican Amber Reveals Springtails’ Longstanding Dispersal by Social Insects

Wednesday, November 27, 2019

Distribution of Electrosminthuridia helibionta springtails on termite and ant hosts within 16-million-year-old Dominican amber: (A) amber specimen; (B) illustration showing the location of springtails on social insects. Arrow – inflow of the tree resin before consolidation. Scale bar – 0.5 cm. Image credit: N. Robin & P. Barden.

An international team of paleontologists has announced the discovery of an ancient interaction preserved in a 16-million-year-old (Miocene Epoch) piece of amber from the Dominican Republic: a winged termite and an ant along with 25 springtails (one of the oldest terrestrial arthropod lineages living today) attached or in close proximity to the wings and legs of their hosts. This discovery highlights the existence of a new type of hitchhiking behavior among wingless terrestrial arthropods, and could be key to explaining how symphypleonan springtails successfully achieved dispersal worldwide.

“The existence of this hitchhiking behavior is especially exciting given the fact that modern springtails are rarely described as having any interspecfic association with surrounding animals,” said Dr. Ninon Robin, a postdoctoral researcher in the Department of Biological Sciences at the New Jersey Institute of Technology.

“This finding underscores how important fossils are for telling us about unsuspected ancient ecologies as well as still ongoing behaviors that were so far simply overlooked.”

Today, springtails (subclass Collembola) are among the most common arthropods found in moist habitats around the world.

Most possess a specialized appendage under their abdomen they use to ‘spring’ away in flee-like fashion to avoid predation.

However, this organ is not sufficient for traversing long distances, especially since most springtails are unable to survive long in dry areas.

The ancient hitchhikers Dr. Robin and colleagues found in the Dominican amber, dubbed Electrosminthuridia helibionta, belong to a lineage of springtails found today on every continent, known as Symphypleona, which may have been pre-adapted to grasping on to other arthropods through prehensile antennae.

Because springtails would have encountered such winged termites and ants frequently due to their high abundance during the time of the preservation, these social insects may have been their preferred hosts for transportation.

“Symphypleonan springtails are unusual compared to other Collembola in that they have specialized antennae that are used in mating courtship,” said Dr. Phillip Barden, from the Department of Biological Sciences at the New Jersey Institute of Technology and the Division of Invertebrate Zoology at the American Museum of Natural History.

“This antennal anatomy may have provided an evolutionary pathway for grasping onto other arthropods.”

“In this particular fossil, we see these specialized antennae wrapping around the wings and legs of both an ant and termite.”

“Some winged ants and termites are known to travel significant distances, which would greatly aid in dispersal.”

The study was published in the journal BMC Evolutionary Biology.

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N. Robin et al. 2019. Fossil amber reveals springtails’ longstanding dispersal by social insects. BMC Evol Biol 19, 213; doi: 10.1186/s12862-019-1529-6

Source: www.sci-news.com/