Scientists unearth a 112-million-year-old time capsule filled with ancient insects

Amber (fossilized tree resin) has been found in samples dating back as far as 320 million years, but it became far more common between 120 million and 70 million years ago, during the Cretaceous era (143.1 million to 66 million years ago). These ancient resins sometimes contain "bio-inclusions" -- trapped remains of plants or animals -- that offer rare, detailed glimpses of life forms such as insects and flowers that are not usually preserved as fossils. Until now, nearly all known major amber deposits were located in the Northern Hemisphere, leaving scientists with limited insight into what Southern Hemisphere ecosystems looked like during the time when the continents were beginning to separate from Gondwana.

To investigate, Xavier Delclòs and his research team examined amber and surrounding rock samples collected from the Genoveva quarry in Ecuador. The amber, dated to roughly 112 million years ago, belongs to the Hollín Formation, a sedimentary layer that stretches across Ecuador's Oriente Basin. The team identified two distinct kinds of amber: one formed underground near the roots of resin-producing plants, and another that developed in the open air. Among 60 samples of the latter, the researchers found 21 bio-inclusions representing five insect orders, including Diptera (flies), Coleoptera (beetles), and Hymenoptera (a group that includes ants and wasps), as well as a fragment of spider web. In addition, the rock surrounding the amber contained numerous plant fossils such as spores, pollen, and other botanical traces.

According to the researchers, the characteristics of the fossils indicate that the amber originated in a warm, humid forest filled with dense vegetation and resin-producing trees in southern Gondwana. They emphasize that this rare find provides a crucial new resource for understanding life and biodiversity during this key period in Earth's history.