10 most difficult pre­his­to­ry riddles

The word mammoth comes from the mythology of the Siberian peoples who believed they lived underground - as dead ones were found in the ground from time to time.

Until about 14,000 years ago, Great Britain was joined to Ireland, and as recently as 8,000 years ago it was joined to the continent by a strip of low marsh leading to what are now Denmark and the Netherlands. Great Britain became an island at the end of the last glacial period when sea levels rose due to the combination of melting glaciers and the subsequent isostatic rebound of the crust.

The Paris Codex is devoted almost entirely to Mayan ritual and ceremony and is one of three surviving generally accepted pre-Columbian Maya books dating to the Period of Mesoamerican chronology (c. 900–1521 AD). The codex largely relates to a cycle of thirteen 20-year k'atuns and includes details of Maya astronomical signs.

The Tomb of Eve is an archeological site located in Jeddah, Saudi Arabia. It is considered by some Muslims to be the burial place of Eve. In 1975, the site was also sealed with concrete by religious authorities, who disapprove of pilgrims praying at tombs. The object is not available to tourists.

The mulberry is a significant fiber crop in the history of paper. It was used for papermaking in China by around 100 AD. The paper recipe used by Cai Lun included plant bark fibres, rags and fishing nets. Early paper makers particularly valued Mulberry for producing high quality paper. Washi, a Japanese handcrafted paper, is made with the inner bark, which is pounded and mixed with water to produce a paste, which is dried into sheets.

The woolly mammoth was the last among mammoth species. They have vanished from Europe and southern Siberia about 10,000 years ago, but a small population survived on the St. Paul Island, Alaska, up until 3750 BC, and the small mammoths of Wrangel Island survived until 1650 BC. They were still around when the Egyptian Pyramids were being built.

'Pharaoh' is the term we use today to describe the rulers of ancient Egypt. Pharaoh' is actually a Greek word that is based on an Egyptian word that meant 'great house'. When this word was first used, it referred to the palace of the king and its greatness, not just to the king himself. We use the word 'pharaoh' today to mean the ruler of ancient Egypt.

The last universal common ancestor (LUCA) is the most recent population of organisms from which all organisms now living on Earth have a common descent. LUCA is not thought to be the first living organism on Earth, but only one of many early organisms, whereas the others became extinct. In 2016 study identified a set of 355 genes inferred to have been present in LUCA. LUCA is estimated to have lived some 3.5 to 3.8 billion years ago in the Paleoarchean era.

Dunkleosteus is an extinct genus of arthrodire placoderm fish that existed during the Late Devonian period, about 358–382 million years ago. Some of which are among the largest placoderms to have ever lived. The largest species, D. terrelli grew up to 6 m (19.7 ft) long and 1 t (1.1 short tons) in weight. Numerous fossils of the various species have been found in North America, Poland, and Morocco.

The archaeological site of El Tajin, located in the present-day Mexican State of Veracruz, is remarkable for many reasons. The site boasts many buildings, temples, palaces and ball courts, but the most impressive of all is the stunning Pyramid of the Niches. El Tajín was named a World Heritage site in 1992, due to its cultural importance and its architecture.