Today is the birthday of naturalist, biologist, geologist, meteorologist, geographer, Karl Ernst von Baer, who is considered the founding father of embryology and was a pioneer in studying biological time – the perception of time (link below) in different organisms. Baer believed in a teleological force in nature which directed evolution (orthogenesis).
Karl Ernst von Baer was born on Tuesday, February 28, 1792, in Jerwen County, Governorate of Estonia (in present-day Lääne-Viru County, Estonia), as a knight by birthright. He was educated at the Knight and Cathedral School in Reval (Tallinn) and the Imperial University of Dorpat (Tartu). In 1812, during his tenure at the university, he was sent to Riga to aid the city after Napoleon's armies had laid siege to it. After leaving Tartu, he continued his education in Berlin, Vienna, and Würzburg, where Ignaz Döllinger introduced him to the new field of embryology.
Von Baer studied the embryonic development of animals, discovering the blastula stage of development and the notochord. Together with Heinz Christian Pander and based on the work by Caspar Friedrich Wolff, he described the germ layer theory of development (ectoderm, mesoderm, and endoderm) as a principle in a variety of species, laying the foundation for comparative embryology in the book Über Entwickelungsgeschichte der Thiere (1828). In 1826, Baer discovered the mammalian ovum. The human ovum was first described by Edgar Allen in 1928. In 1827, he completed research Ovi Mammalium et Hominis genesi for St Petersburg's Academy of Science (published at Leipzig). In 1827 von Baer became the first person to observe human ova.
Baer was a genius scientist covering not only the topics of embryology and ethnology, he also was especially interested in the geography of the
northern parts of Russia, and explored Novaya Zemlya in 1837. In these arctic environments, he was studying periglacial features, permafrost occurrences, and collecting biological specimens.
Baer summarized his knowledge in 1842/43 in a print-ready typescript.
The German title is Materialien zur Kenntniss des unvergänglichen
Boden-Eises in Sibirien (Materials for the Knowledge of the Perennial
Ground Ice in Siberia). This world's first permafrost textbook was
conceived as a complete work for printing. But it remained lost for more
than 150 years.
From his studies of comparative embryology, Baer had believed in the transmutation of species but rejected later in his career the theory of natural selection proposed by Charles Darwin.
According to Darwin:
- "Von Baer, towards whom all zoologists feel so profound a respect, expressed about the year 1859... his conviction, chiefly grounded on the laws of geographical distribution, that forms now perfectly distinct have descended from a single parent-form."
In 1849, Baer was elected a foreign honorary of the American Academy of Arts and Sciences. He was elected a foreign member of the Royal Swedish Academy of Sciences in 1850. In 1852, he was conferred the title of Honorary Fellow of the University of Tartu. He was the president of the Estonian Naturalists' Society in 1869–1876, and was a co-founder and first president of the Russian Entomological Society. In 1875, he became a foreign member of the Royal Netherlands Academy of Arts and Sciences.
Before the Estonian conversion to the euro, the 2-kroon bank note bore his portrait . . .
. . . and a duck, Baer's pochard, was named after him.
Karl Ernst von Baer died in Dorpat (now Tartu, Estonia) of natural causes on November 28, 1876, at the age of 84.
Viewfinder links:
Hektoen International ~ Evolution from recapitulation theory to Neural Darwinism
International Journal of Biology ~ Karl Ernst von Baer and Evolution
National Library of Medicine ~ Fertilization and the transition from meiosis to mitosis
Oxford Academic ~ An historical look at embryo transfer UC Berkeley Press ~ A Synthesis of Anti-Darwinian Arguments: Karl Ernst von Baer in the 1870s
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