Canada, Mars, Plants
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Mummified wood

Mummified wood are fossils of wood that have not permineralized. They are formed when trees are buried rapidly in dry cold or hot environments. They are valued in paleobotany because they retain original cells and tissues capable of being examined with the same techniques used with extant plants in dendrology.

The most important conditions required for mummification are an absence of microbial and chemical degradation, and burial conditions where mineral-bearing groundwater is unable to penetrate the tissues. Mummified wood consists of original tissues that have undergone minimal degradation of cellular constituents. This preservation is a result of several factors: inhibition of wood-destroying microbes, decreased oxygen availability, and the absence of harsh chemical or physical conditions (e.g., high alkalinity or acidity, or elevated temperatures). Environments that favor mummification include deeply submerged wood, burial in impermeable sediments, aridity, or low temperatures.

  • Mustoe GE. Non-Mineralized Fossil Wood. Geosciences. 2018; 8(6):223. https://doi.org/10.3390/geosciences8060223 “This paper provides a detailed review of fossil wood occurrences where tissues have not been mineralized. These fossils are sometimes described as “carbonized wood”, but unmineralized ancient wood can be divided into three categories. Mummified wood consists of original tissues that may have undergone anatomical distortion or desiccation, but which are otherwise free of alteration. Charcoalified wood originates when wood is combusted in an anaerobic environment, causing much of the organic materials to be reduced to pure carbon. Coalified wood consists of tissues that have been altered by heat and pressure during deep burial, converting the original organic constituents to a mixture of pure carbon and various hydrocarbons”
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Lignin and cellulose, the primary constituents of wood, may undergo alteration on a microscopic level, even though the overall appearance of the ancient wood may appear unchanged. Wood cell walls consist of an outer primary wall that encloses a multilayered secondary wall. The primary wall, which may be relatively thick, consists mostly of cellulose and hemicellulose, in contrast to the thinner secondary wall that is largely composed of a mixture of cellulose and lignin. This secondary wall commonly consists of three discrete layers (lamellae) that differ in the orientation of their cellulosic aggregates and the degree of lignification. Microbial degradation of wood may result in destruction of the wood sugars cellulose and hemicellulose, resulting in relative enrichment of lignin.

  • Mustoe GE. Non-Mineralized Fossil Wood. Geosciences. 2018; 8(6):223. https://doi.org/10.3390/geosciences8060223 “This paper provides a detailed review of fossil wood occurrences where tissues have not been mineralized. These fossils are sometimes described as “carbonized wood”, but unmineralized ancient wood can be divided into three categories. Mummified wood consists of original tissues that may have undergone anatomical distortion or desiccation, but which are otherwise free of alteration. Charcoalified wood originates when wood is combusted in an anaerobic environment, causing much of the organic materials to be reduced to pure carbon. Coalified wood consists of tissues that have been altered by heat and pressure during deep burial, converting the original organic constituents to a mixture of pure carbon and various hydrocarbons”
    • Barghoorn, E. Degradation of plant tissues in organic sediments. J. Sediment. Petrogrol. 1952, 2, 34–41. [Google Scholar]
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Figure 1. Anatomical preservation in mummified food from western Washington, USA. (A,B) Transverse views, late Pleistocene wood, Whidbey Formation, Swantown, Whidbey Island, Island County, Washington State, USA. (C) Transverse view, Wilkes Formation compressed wood. (D) Late Pleistocene wood showing extensive decay. Radial view. Net-like structures are relict ray cell walls, Whidbey Formation, Cama Beach, Camano Island, Island County, Washington, USA. Mustoe GE. Non-Mineralized Fossil Wood. Geosciences. 2018; 8(6):223. https://doi.org/10.3390/geosciences8060223

Deterioration of the lignin-rich secondary wall may not greatly disrupt the overall cellular architecture as long as the cellulosic outer walls remain relatively intact (Figure 1). When it is preserved, cellulose has scientific value because carbon and oxygen isotope ratios in this substance can be used to estimate paleoprecipitation and paleotemperature.

  • Mustoe GE. Non-Mineralized Fossil Wood. Geosciences. 2018; 8(6):223. https://doi.org/10.3390/geosciences8060223 “This paper provides a detailed review of fossil wood occurrences where tissues have not been mineralized. These fossils are sometimes described as “carbonized wood”, but unmineralized ancient wood can be divided into three categories. Mummified wood consists of original tissues that may have undergone anatomical distortion or desiccation, but which are otherwise free of alteration. Charcoalified wood originates when wood is combusted in an anaerobic environment, causing much of the organic materials to be reduced to pure carbon. Coalified wood consists of tissues that have been altered by heat and pressure during deep burial, converting the original organic constituents to a mixture of pure carbon and various hydrocarbons.”
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Notable examples include the mummified forests in Ellesmere Island and Axel Heiberg Island.

Axel Heiberg Island (Inuktitut: ᐅᒥᖕᒪᑦ ᓄᓈᑦ, Umingmat Nunaat) is an uninhabited island in the Qikiqtaaluk Region, Nunavut, Canada. Located in the Arctic Ocean, it is the 32nd largest island in the world and Canada’s seventh largest island. According to Statistics Canada, it has an area of 43,178 km2 (16,671 sq mi). It is named after Axel Heiberg.

Not to be confused with Heiberg Islands, which are named after the same person

One of the larger members of the Arctic Archipelago, it is also a member of the Sverdrup Islands and Queen Elizabeth Islands. It is known for its unusual fossil forests, which date from the Eocene period. Owing to the lack of mineralization in many of the forest specimens, the traditional characterization of “fossilisation” fails for these forests and “mummification” may be a clearer description. The fossil records provide strong evidence that the Axel Heiberg forest was a high-latitude wetland forest.

During the summer of 1986, a Canadian expedition headed by Dr. James Basinger set out to investigate a very unusual fossil forest on Axel Heiberg. The findings of these and subsequent expeditions have since been popularly reported in Canada. Over 40 million years ago during the Eocene epoch, a forest of tall trees flourished on Axel Heiberg Island. The trees reached up to 35 m (115 ft) in height; some may have grown for 500 to 1,000 years. At the time, the polar climate was warm, but the winters were still continuously dark for three months. As the trees fell, the fine sediment in which the forest grew protected the plants. Instead of turning into petrified “stone” fossils, they were ultimately mummified by the cold, dry Arctic climate, and only recently exposed by erosion. Scientists from the Komarov Botanical Institute of the Russian Academy of Sciences in Saint Petersburg provided a few grams of Metasequoia conifer wood from the site to genetics researchers at the National University of Altai, who compared the DNA sequences of the ancient wood with DNA of modern woody plants and found them to be almost identical. Komarov Institute scientists also discovered double strand DNA molecules in Metasequoia fossil leaves from Axel Heiberg Island.

As late as 1999, the preservation of this unique site was a concern, as the fossil wood was easily damaged and eroded once exposed. There were concerns that wood was being taken by Arctic cruise ship tourists, and that the site was being disturbed by Canadian military helicopters from a nearby base, and even by scientists themselves in their studies. There were calls for more protection for the area. It currently has no official status, in part because land claims had to be settled. But now Nunavut is looking at how best to protect the fossil forest, possibly by setting up a territorial park to be called Napaaqtulik, “where there are trees”.

Interesting animal fossils have been discovered on the island, including a remarkably preserved specimen of an ancient Aurorachelys turtle and, identified in 2016, the humerus of a Tingmiatornis bird.

Lost Hammer Spring

The Lost Hammer Spring, located in the central west region of the island (79°07′N 090°21′W) is the coldest and saltiest of all Arctic springs described to date. It is characterized by a perennial hypersaline (24%) discharge at subzero temperatures (~−5 °C (23 °F)) flowing to the surface through a hollow, 2 m (6 ft 7 in) high cone-shaped salt tufa structure. Continuous gas emissions from the spring indicate an underlying thermogenic methane source. On the basis of these properties, this spring is considered a significant astrobiology analogue site for possible habitats currently present on Mars and the cold moons Europa and Enceladus.

Microbes have been found at this site which do not depend on organic material or oxygen, but only on simple inorganic compounds. These inorganic compounds are present on Mars.

Ellesmere Island (Inuktitut: ᐅᒥᖕᒪᒃ ᓄᓇ, romanized: Umingmak Nuna, lit. ‘land of muskoxen‘; French: île d’Ellesmere) is Canada’s northernmost and third largest island, and the tenth largest in the world. It comprises an area of 196,236 km2 (75,767 sq mi), slightly smaller than Great Britain, and the total length of the island is 830 km (520 mi).

Lying within the Arctic Archipelago, Ellesmere Island is considered part of the Queen Elizabeth Islands. Cape Columbia at 83°06′ is the northernmost point of land in Canada and one of the northernmost points of land on the planet (the northernmost point of land on Earth is the nearby Kaffeklubben Island of Greenland).

The Arctic Cordillera mountain system covers much of Ellesmere Island, making it the most mountainous in the Arctic Archipelago. More than one-fifth of the island is protected as Quttinirpaaq National Park.

In 2021, the population of Ellesmere Island was recorded at 144. There are three settlements: Alert, Eureka, and Grise Fiord. Ellesmere Island is administered as part of the Qikiqtaaluk Region in the Canadian territory of Nunavut.

History

The first human inhabitants of Ellesmere Island were small bands drawn to the area for Peary caribou, muskox, and marine mammal hunting about 2000–1000 BCE. – As was the case for the Dorset (or Paleo-Eskimo) hunters and the pioneering Neo-Eskimos, the post-Ruin Island and Late Thule culture Inuit used the Bache Peninsula region extensively both summer and winter until environmental, ecological, and possibly social circumstances caused the area to be abandoned. It was the last region in the Canadian High Arctic to be depopulated during the Little Ice Age, attesting to its general economic importance as part of the Smith Sound culture sphere of which it was occasionally a part and sometimes the principal settlement component.

  • Civilization.ca. “Arctic History”. Archived from the original on September 23, 2008.
  • Schledermann, Peter; McCullough, Karen Margrethe (2003). Late Thule culture developments on the central east coast of Ellesmere Island. Copenhagen, Denmark: Danish Polar Center. ISBN 978-87-90369-64-4.

Vikings from the Greenland colonies reached Ellesmere Island, Skraeling Island, and Ruin Island during hunting expeditions and trading with the Inuit groups. Unusual structures on Bache Peninsula may be the remains of a late-period Dorset stone longhouse.

  • Schledermann, Peter; McCullough, Karen Margrethe (2003). Late Thule culture developments on the central east coast of Ellesmere Island. Copenhagen, Denmark: Danish Polar Center. ISBN 978-87-90369-64-4.
  • Schledermann, Peter (May 1981). “Eskimo and Viking Finds in the High Arctic”. National Geographic. 159 (5): 584.

The first European to sight the island after the height of the Little Ice Age was William Baffin in 1616. Ellesmere Island was named in 1852 by Edward Inglefield‘s expedition after the English politician Francis Egerton, 1st Earl of Ellesmere, who was President of the Royal Geographical Society from 1853 to 1855. The United States expedition led by Adolphus Greely in 1881 crossed the island from east to west,  establishing Fort Conger in the northern part of the island. The Greely expedition found fossil forests on Ellesmere Island in the late 1880s. Stenkul Fiord was first explored in 1902 by Per Schei, a member of Otto Sverdrup‘s 2nd Norwegian Polar Expedition.

Schei and later Alfred Gabriel Nathorst described the Paleocene–Eocene (ca. 55 Ma) fossil forest in the Stenkul Fiord sediments. The Stenkul Fiord site represents a series of deltaic swamp and floodplain forests. The trees stood for at least 400 years. Individual stumps and stems of >1 m (>3 ft) diameter were abundant, and are identified as Metasequoia and possibly Glyptostrobus. Well preserved Pliocene peats containing abundant vertebrate and plant macrofossils characteristic of a boreal forest have been reported from Strathcona Fiord.

The Ellesmere Ice Shelf was documented by the British Arctic Expedition of 1875–76, in which Lieutenant Pelham Aldrich‘s party went from Cape Sheridan (82°28′N 61°30′W) west to Cape Alert (82°16′N 85°33′W), including the Ward Hunt Ice Shelf. In 1906 Robert Peary led an expedition in northern Ellesmere Island, from Cape Sheridan along the coast to the western side of Nansen Sound (93°W). During Peary’s expedition, the ice shelf was continuous; it has since been estimated to have covered 8,900 km2 (3,400 sq mi). The ice shelf broke apart in the 20th century, presumably due to climate change.

In 2006, University of Chicago paleontologist Neil Shubin and Academy of Natural Sciences paleontologist Ted Daeschler reported the discovery of the fossil of a Paleozoic (ca. 375 Ma) fish, named Tiktaalik roseae, in the former stream beds of Ellesmere Island. The fossil exhibits many characteristics of fish, but also indicates a transitional creature that may be a predecessor of amphibians, reptiles, birds, and mammals, including humans.

In 2011, Jason P. Downs and co-authors described the sarcopterygian Laccognathus embryi from specimens collected from the same locality that Tiktaalik was found.

In 2015, the Earth’s geomagnetic north pole was located at approximately 80.37°N 72.62°W, on Ellesmere Island.

Ellesmere Island is the setting of much of Melanie McGrath’s The Long Exile: A True Story of Deception and Survival Amongst the Inuit of the Canadian Arctic about the High Arctic relocation, and also of her Edie Kiglatuk mystery series.

In the 2013 American superhero film Man of Steel, Ellesmere Island was the site of a combined United States-Canadian scientific expedition to recover an ancient Kryptonian spaceship buried in the glacial ice pack.

The island was the location for the 2014 BBC programme Snow Wolf Family and Me.

Ellesmere Island (and in particular the Milne ice shelf) is a main location in Dan Brown‘s novel Deception Point.

The 2008 documentary Exile by Zacharias Kunuk documents the experiences of Inuit families who were forcibly relocated to Ellesmere island in the 1950s to ‘settle’ it for the Canadian government. The families discuss being deceived by the Canadian government about the conditions and terms of where they were going and having to endure years of surviving in inhospitable conditions with little food or water.

Further reading

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