Today in Science History – January 10 – Carolus Linnaeus

Carl von Linné, also known as Carl Linnaeus
Carl von Linné (1707 – 1778)

January 10 marks the passing of Carolus Linnaeus or Carl von Linné. Linnaeus was a Swedish biologist who introduced the taxonomy scheme used for naming plants and animals. Linnaeus’ binomial nomenclature names an animal by two parts: genus and species. Humans become Homo Sapiens, foxes became Vulpis vulpis, and house cats become Felis catus.

Linnaeus took great pride in his work. His “Systema Naturae” book underwent many additions and introduced cover art that depicted a man giving names to animals as God created them. He was also known for the phrase “Deus creavit, Linnaeus disposuit” which is Latin for “God Creates, Linnaeus organizes”.

The Linnaean taxonomy arranges all biological creatures into three kingdoms: animals, vegetables (plants), and minerals. Each kingdom is broken into classes unique to each kingdom. The animal kingdom was divided into six classes: Mammalia (mammals), Aves (birds), Amphibia (amphibians), Pisces (fish), Insecta (insects), and Vermes (worms, snails, mollusks, jellyfish, and other soft-bodied slow-moving creatures). The vegetable kingdom was divided into 26 different classes based mainly on the number of stamens and pistils. The mineral kingdom had four classes including Petrae (rocks), Minerae (salts and metal minerals), Fossilia (fossils), and Vitamentra (minerals with nutritive properties).

Each class is further broken into orders. Orders are broken into genera (plural of genus). Genera are broken into species. Depending on the species, there could be one more subset below species.

A Linnaean name is typically given in two parts: Genus followed by species. The Genus is capitalized and species in lower-case. In print, this name is italicized. It’s enough to give first-year biology students nightmares.

This system allowed scientists to identify species across regions without the confusion that can arise from common names for the same species. For example: A daffodil is called suisen in Japan and narges in Hindi and Persian. These common names are all associated with the species narcissus which includes over 300 different flowers. The Linneaus classifications lets any scientist tell the difference between Narcissus calcicola and Narcissus rupicola. Both flowers look like ‘daffodils’ but have distinct differences.

Linnaeus was also the person who reversed Anders Celsius‘ temperature scale. Celsius’ original temperature scale ranged from boiling water at 0 °C and freezing water at 100 °C. Linnaeus swapped those endpoints to the more familiar 0 °C of freezing point and 100 °C boiling point so the temperatures increase as their numerical value increase.

Notable Science History Events for January 10

1997 – Alexander Robertus Todd died.

Alexander Robertus Todd
Alexander Robertus Todd (1907 – 1997)
Nobel Foundation

Todd was a Scottish biochemist who was awarded the 1957 Nobel Prize in Chemistry for his work with nucleotides, nucleosides and their co-enzymes. He studied the structure and synthesis of many of these compounds that are the building blocks of DNA and RNA. He also synthesized two important biochemical compounds: adenosine triphosphate or ATP and flavin adenine dinucleotide or FAD.

1946 – Project Diana successfully detects radar from the Moon.

Project Diana antenna
Project Diana radar array antenna.

The U.S. Army Signal Corps conducted the first radio astronomy experiment called Project Diana. They transmitted a signal at the Moon and detected the reflected signal. Their radar array could only be aimed through the azimuth angles so they had to wait for the Moon to pass in front. They sent radio pulses towards the Moon and received a signal back 2.5 seconds later after. 

The success of this experiment opened the way for using the Moon to relay radio signals over the horizon. The signals would often come in faint and required large receivers and transmitters but it worked. Earth-Moon-Earth transmissions were eventually replaced by communication satellites.

1936 – Robert Woodrow Wilson was born.

Wilson is an American astronomer who shares half the 1978 Nobel Prize in Physics with Arno Allan Penzias for the discovery of the Cosmic Microwave Background radiation. CMB radiation is the background radio ‘noise’ that is believed to be the remnant radiation from the Big Bang.

1916 – Sune K. Bergström was born.

Bergström was a Swedish biochemist who shares the 1982 Nobel Prize in Medicine with Bengt Samuelsson and John R. Vane for their discoveries concerning prostaglandins and related substances. Prostaglandins are biochemical compounds that influence physiological phenomena such as blood pressure, body temperature, and allergic reactions.

1770 – Carolus Linnaeus died.

1654 – Nicholas Culpeper died.

Nicholas Culpeper
Nicholas Culpeper (1616 – 1654)

Culpeper was an English physician and herbalist who documented the medicinal benefits of several English herbs. His Complete Herbal, published in 1653, was an attempt to provide medical information to the general public to treat their own sicknesses and ailments. This book is one of the most successful non-religious English books ever written and is still in print today.