Forests in polar regions

Metasequoia occidentalis

The genus Metasequoia was common in the northern regions of the Northern Hemisphere during the Paleogene and Neogene periods. Today it remains only in China, for reasons not yet understood by scientists.

Fossils of Metasequoia were known before any living members of the genus were discovered in nature. The first fossil was found in Japan in 1941. Three years later, a previously unknown tree was discovered in a small grove in Hubei, China. It turned out to be the same species as the fossil from Japan, and in 1948 the Hubei tree was determined to be a living Metasequoia.

The genus Metasequoian belongs to the cypress family. Members of this family are found in various environments — everything from semi-arid desert to marshland forest.  Some genera of this family formed the coal deposits in Europe.

Quercus furujhelmii

Large jagged oak leaves like this indicate that the climate in Alaska was warmer and damper around 20 million years ago.

Juglans nigella

This leaf is from a tree of the walnut genus. It was found in Alaska, but the same species is also known to have grown on Greenland; scientists have found fossilized leaves and fruit of the tree there.

Unlike today, different walnut species once grew in the Arctic, which was warmer during the Paleogene. Today they are found in Europe, Asia and North America.

Betula grandifolia

 Betula grandifolia is a large-leafed birch from Alaska.

The birch family includes the alder, hazel and birch genera. Existing birch species evolved around 50 million years ago. Birches with large, broad leaves were also widespread at that time; but they disappeared from many areas at the end of the Neogene Period.

Today, various species of birch grow throughout the Northern Hemisphere. Large-leaved species remain only in warm, damp regions such as the southeastern United States, parts of Mexico and in Southeast Asia.

Baltic amber

Baltic amber is tree resin that was fossilized around 50 million years ago in the Baltic and some other regions. Scientists originally believed that amber formed from the resin of pine trees. But it is now known that the resin comes from trees of the genus Sciadopytis, which today grows only in Japan.

During the Paleogene and Neogene periods, it grew as far north as Iceland and Greenland.It is still not known why large quantities of amber formed in the Baltic Region. One theory is that coniferous trees covering a large area were infected by a disease that caused them to produce enormous volumes of resin. Whatever the cause, a great many insects got stuck in the sticky resin and, as a result, extremely well-preserved fossils of insects can now be found in amber.

Glyptostrobus europaeus

A twig with immature seed cones can be seen on this fossil.

Glyptostrobus grew across much of the Earth during the Palaeogene and Neogene periods. Today it remains only in Southeast Asia. Coal deposits of Europe have formed from the remains of forests of Glyptostrobus.

Taxodium dubium

Taxodium, a member of the cypress family, was common in the Northern Hemisphere during the Palaeogene and Neogene periods.

Today, there are relatives remaining in Mexico and the southeastern United States. In Florida it is called swamp cypress because it can survive with its roots immersed in water, and in Mexico it grows along the banks of rivers.

Alnus carpinoides

 Alnus carpinoides was a tree that grew along lakes and rivers.

Taxodium dubium

Taxodium, a member of the cypress family, was common in the Northern Hemisphere during the Palaeogene and Neogene periods.

Today, there are relatives remaining in Mexico and the southeastern United States. In Florida it is called swamp cypress because it can survive with its roots immersed in water, and in Mexico it grows along the banks of rivers.

Metasequoia occidentalis

The genus Metasequoia was common in the northern regions of the Northern Hemisphere during the Paleogene and Neogene periods. Today it remains only in China, for reasons not yet understood by scientists.

Fossils of Metasequoia were known before any living members of the genus were discovered in nature. The first fossil was found in Japan in 1941. Three years later, a previously unknown tree was discovered in a small grove in Hubei, China. It turned out to be the same species as the fossil from Japan, and in 1948 the Hubei tree was determined to be a living Metasequoia.

The genus Metasequoian belongs to the cypress family. Members of this family are found in various environments — everything from semi-arid desert to marshland forest.  Some genera of this family formed the coal deposits in Europe.