Progress has been made in the study of tooth growth and development in ancient humans in East Asia

development of teeth is of great significance to understanding the evolution of human life history. Recently, the Chinese Academy of Sciences Institute of Paleontology and Paleoanthropology Associate Researcher Yu Song and other foreign researchers have completed a study on the tooth growth and development of ancient human infants in Xujia kiln, Hebei Province, China, the results of January 17 with "the first systematic analysis of the growth and development of ancient human teeth in East Asia" published online in the journal Scientific Progress.
from other primates that are present, modern people have a unique, long physiological system growth and development period. The specific performance is that the childhood period is long, the first birth period is late, the life span is long, etc. In addition to the identification criteria in morphology, genetics, behavior and so on, growth and development is also an important indicator of modern human judgment. For a long time, because soft tissue is difficult to preserve in the fossil record, teeth have become an important research material to understand the evolution of human growth and development.
Said, teeth as a research material has two major advantages, first, teeth in the growth process, retain the short cycle line in days and in many days as a long cycle line, observe these long cycle lines, can restore its growth trajectory;
studies show that the growth and development of southern ancient apes, early African genus and Erectine teeth are faster, which is different from that of modern humans. Some growth and development indicators of Neanderthal teeth have entered the range of modern human variation, but there are still significant differences with modern people. The performance of ancient humans in the growth and development of teeth after Homo erectus and before Homo erectus has always been an open mystery.
Yu Song introduced, in the Chinese fossil record, just preserved a piece of young individual upper jaw bone material from the site of Xujia kiln in Hebei Province, its first molar teeth just sprouted soon, the other front teeth, canine teeth, front molars and second molars are still in the jaw bone is not sprouted or is about to germinate. "This is an important material for understanding the growth and development of human teeth during this period." Yu Song told China Science Daily.
researchers used synchronous radiation and other techniques to quantitatively study the growth and development of ancient humans at The Xujia kiln site. Dating shows that Xujia kiln people lived 148-248,000 years ago or 10.4-125,000 years ago, in the middle and late 1980s, which is one of the key points in the origin of modern man. A series of studies on the evolutionary status of Xujia kilns show that they represent transitional ancient humans, whose morphological characteristics have mosaics, both the original characteristics of Homo erectus and the progressive characteristics of Homo erectus, as well as the high-frequency characteristics of Neanderthals.
The study further restores the growth and development of ancient human teeth at the Xujia kiln site (thought to reflect the history of life) and finds that they have entered the range of modern human variation, suggesting that humans may have followed a slower circadian rhythm as modern humans did before evolving into what they are today. (Source: Science Network, Buye)