The first ever piece of the Antarctic amber was found in a sediment core from the mid-shelf section of Pine Island trough in Antarctica.
Pine Island amber. Scale bars – 50 μm. Image credit: Klages et al., doi: 10.1017/S0954102024000208.
“Resin is a direct plant product defined as a lipid-soluble mixture of volatile and non-volatile compounds usually exuded within a plant or at its surface, predominantly by gymnosperms,” said lead author Dr. Johann Klages from the University of Bremen and colleagues.
“Some plant resins are able to fossilize under certain conditions and get preserved in the geological record as amber.”
“Until now, the southernmost amber finds are of mid-Cretaceous age and have been discovered in the Otway basin in southern Australia (Otway amber) and as part of the Tupuangi Formation on the Chatham Islands, New Zealand (Tupuangi amber), respectively.”
The first Antarctic amber was recovered by the MARUM-MeBo70 seafloor drill rig from the mid-shelf section of Pine Island trough in the Amundsen Sea Embayment, West Antarctica, during RV Polarstern Expedition in early 2017.
Dubbed Pine Island amber, the specimen is mid-Cretaceous in age, between 92 and 83 million years old.
The discovery indicates a swampy temperate rainforest environment near the south pole that was dominated by conifers.
“The Antarctic amber likely contains remains of original tree bark as micro-inclusions,” said co-author Dr. Henny Gerschel, a researcher at the Saxon State Office for the Environment, Agriculture and Geology.
“Considering its solid, transparent and translucent particles, the amber is of high quality, indicating its burial near the surface, as amber would dissipate under increasing thermal stress and burial depth.”
“We also found indications for pathological resin flow — a strategy trees use to seal damaged bark induced by parasites or wildfires, hence creating a chemical and physical barrier protecting from insect attacks and infections.”
“Our discovery is another piece of the puzzle and will help us gaining a better understanding of the swampy, conifer-rich, temperate rainforest environment identified near the south pole during the mid-Cretaceous.”
“It was very exciting to realize that, at some point in their history, all seven continents had climatic conditions allowing resin-producing trees to survive,” Dr. Klages said.
“Our goal now is to learn more about the forest ecosystem — if it burned down, if we can find traces of life included in the amber.”
“This discovery allows a journey to the past in yet another more direct way.”
A paper reporting the discovery was published today in the journal Antarctic Science.
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Johann P. Klages et al. First discovery of Antarctic amber. Antarctic Science, published online November 12, 2024; doi: 10.1017/S0954102024000208
Source : Breaking Science News