Whose Wednesday: Torbern Bergman

by Piter Kehoma Boll

Today I am presenting a 18th century scientist who worked on several areas of the natural sciences.

Torbern Olaf Bergman was born on 20 March 1735 in Låstad parish, Sweden, the son of Barthold Bergman and Sara Hägg. His interest in botany was raised by his teacher Sven Hof at Katedralskolan in Skara.

At the age of 17, he enrolled at the University of Uppsala. He wanted to study mathematics and natural science, but his father wanted him to study law or divinity. Trying to please both his father and himself, he overworked himself and became ill, which forced him to stay some time away from study. During this period, he entertained himself with field botany and entomology.

Portrait of Torbern Bergman by Ulrika Pasch.

Through his entomological collections, Bergman became acquainted with Linnaeus and sent him several insects of new species. In 1756, he succeeded in proving that, contrary to Linnaeus’ opinion, the species called Coccus aquaticus was simply the ovum of a leech, which Linnaeus recognized as correct. Due to this discovery, as well as because he developed a method to capture the wingless females of winter moths, Bergman was awarded a prize by the Swedish Academy of Sciences, being elected a member of the Academy in 1764. The next year he was ellected a Fellow of the Royal Society of London.

Bergman also defended a thesis in astronomy and founded the Cosmography Society in Uppsala, through which the published, in 1766, his work Physisk beskrifning öfver jordklotet (Physical description over the globe), which was one of the first books of modern geography. He then became an associate professor of physics and studied the electrical properties of tourmaline, as well as meteorological phenomena such as the northern lights, thunder and rainbow.

In 1767, the chemist Johan Gottschalk Wallerius resigned from his position as professor of chemistry and mineralogy at the University of Uppsala and Bergman was decided to be a candidate. However, he did not have previous experience in publishing works on chemistry and his competitors charged him with ignorance on the subject. To refute them, he isolated himself in a laboratory for some time and wrote a treatise on the manufacture of alum and it became a standard work. Nevertheless, he still faced strong opposition and only got the chair of chemistry through the influence of the prince Gustavus III, who was also chancellor of the university. He kept this position until his death.

Bergman married his wife, Margareta Catharina Trast, in 1771. In 1772, he was one of the first to receive the Royal Order of Vasa, which was awarded to Swedish citizens for their service to the state and society, especially in the fields of agriculture, mining and commerce.

In 1775, Bergman published his most important chemical paper, Essay on Elective Attractions, a study of chemical affinity. In March 1782, he was elected a foreign associate of the French Academy of Sciences.

He died prematurely on 8 July 1784, aged 49, in Medevi, Sweden, due to a stroke. The radiactive uranium mineral torbernite was named in his honor.

– – –

Like us on Facebook!

Follow us on Twitter!

– – –

References:

Encyclopædia Brittanica (1991) Bergman, Torbern Olof. Available at < https://en.wikisource.org/wiki/1911_Encyclop%C3%A6dia_Britannica/Bergman,_Torbern_Olof >. Acess on 20 March 2019.

Wikipedia. Torbern Bergman. Available at < https://en.wikipedia.org/wiki/Torbern_Bergman >. Access on 20 March 2019.

Wikipedia (in Swedish). Torbern Bergman. Available at < https://sv.wikipedia.org/wiki/Torbern_Bergman >. Access on 20 March 2019.

Advertisements

Leave a comment

Filed under Biographies

Friday Fellow: Imperial Fritillary

by Piter Kehoma Boll

Let’s bring a high dose of beauty into today’s Friday Fellow with a wonderful species that may sometimes be found in your garden.

Imperial fritillary growing in its natural environment in Kurdistan. Photo by Wikipedia user A2raya07.*

Fritillaria imperialis, the imperial fritillary or crown imperial, is native from Asian highlands between Turkey and the Himalayas but is cultivated worldwide, having a series of artificially selected cultivars. The plant reaches a height of about 1 m and has a series of lance-shaped leaves along its stem, similarly to what is found in other species of the lily family, Liliaceae, to which it belongs. The flowers appear in a whorl close to the top of the stem and face downwards. A crown of small leaves tops the flowers, hence its name imperialis. The bell-shaped flowers are usually orange in the wild but, in cultivars, they vary between red and yellow.

A cultivar named ‘Rubra Maxima’. Photo by Hendry Heatly.**

The imperial fritillary has been used in traditional medicine for centuries by people living around its native range. Recent studies revealed that the plant contains a series of alkaloids, mostly anticholinergic steroidal alkaloids, which have the potential to be used for the development of new medicines to treat several conditions.

Despite its popularity as an ornamental plant, wild populations of the imperial fritillary are endangered in many countries in which it occurs, especially due to habitat loss. In order to aid in the preservation and restoration of wild populations, some laboratory techniques have been developed to generate clones that could help increase population size in the wild.

– – –

Like us on Facebook!

Follow us on Twitter!

– – –

References:

Akhtar MN, Rahman A, Choudhary MI, Sener B, Erdogan I, Tsuda Y (2003) New class of steroidal alkaloids from Fritillaria imperialis. Phytochemistry 63: 115–122. doi: 10.1016/S0031-9422(02)00569-1

Gilani AH, Shaheen F, Christopoulos A, Mitchelson F (1997) Interaction of ebeinone, an alkaloid from Fritillaria imperialis, at two muscarinic acetylcholine receptor subtypes. Life Sciences 60 (8): 535–544. doi:
10.1016/S0024-3205(96)00691-1

Kiani M, Mohammadi S, Babaei A, Sefidkon F, Naghavi MR, Ranjbar M, Razavi SA, Saeidi K, Jafari H, Asgardi D, Potter D (2017) Iran supports a great share of biodiversity and floristic endemism for Fritillaria spp. (Liliaceae): A review. Plant Diversity 39(5): 245–262. doi: 10.1016/j.pld.2017.09.002

Mohammadi-Dehcheshmeh M, Khalighi A, Naderi R, Sardari M, Ebrahimie E (2008) Petal: a reliable explant for direct bulblet regeneration of endangered wild populations of Fritillaria imperialis L. Acta Physiologiae Plantarum 30(3): 395–399. doi: 10.1007/s11738-007-0126-2

Wikipedia. Fritillaria imperialis. Available at < https://en.wikipedia.org/wiki/Fritillaria_imperialis >. Access on 11 February 2019.

– – –

*Creative Commons License This work is licensed under a Creative Commons Attribution-ShareAlike 3.0 Unported License.

**Creative Commons License This work is licensed under a Creative Commons Attribution-Share Alike 2.0 Generic License.

Leave a comment

Filed under Botany, Friday Fellow

Whose Wednesday: Jean-Louis Petit

by Piter Kehoma Boll

Today we celebrate the birthday of a French scientist and surgeon that achieved a great renown during his time.

Jean-Louis Petit, usually known as Petit the surgeon, was born on 13 May 1674 in Paris. He was interested in anatomy since childhood and received lessons on the subject from the anatomist Alexis Littré, who lived in his house. When Petit was only 12 years old, Littré trusted him his anatomical theater.

After studying surgery with the surgeon Georges Mareschal, Petit obtained the title of master in surgery in 1700. In 1705, he published a work entitled L’Art de guérir les maladies des os (The art of curing bone diseases), which would be translated into English in 1726.

Portrait of Jean-Louis Petit by Ambroise Tardieu.

In 1715, he became a member of the French Royal Academy of Sciences and, in 1731, was named, by the King Louis XV, director of the Royal Academy of Surgery after its foundation.

Petit’s reputation was achieved due to his talent and experience, especially because of his case reports of bleeding, lacrimal fistulas and operations on the frenum of the penis, as well as his work on bone diseases. Due to his fame, he was invited to Poland in 1726 to treat King Augustus II, and to Spain in 1735 to treat Prince Ferdinand VI. Both offered great advantages for him to stay in their countries, but he decided to return to France.

Petit is also acknowledged for the first broad clinical description of an epidural hematoma and its treatment by trepanning at the opposite side of the beginning of neurological signs.

Petit died in Paris on 20 April 1750, aged 76.

– – –

Like us on Facebook!

Follow us on Twitter!

– – –

Reference:

Wikipédia (in French). Jean-Louis Petit (anatomiste). Available at < https://fr.wikipedia.org/wiki/Jean-Louis_Petit_(anatomiste) >. Access on 13 March, 2019.

Leave a comment

Filed under Biographies

Friday Fellow: Platine Shield Harvestman

by Piter Kehoma Boll

Beneath fallen logs and rocks or in the leaf litter of forests and gardens around the La Plata River in Argentina and Uruguay, you may find today’s fellow. Scientifically known as Discocyrtus prospicuus, it is a harvestman, a member of a group of arachnids that resemble spiders. As usual among small hidden invertebrates, it lacks a common name, so I coined the term Platine shield harvestman to refer to it.

Discocyrtus prospicuus in Buenos Aires, Argentina. Photo by Nicolas Olejnik.*

The Platine shield harvestman belongs to the family Gonyleptidae, which includes harvestmen with astonishing armored bodies and a prosoma (or cephalothorax) with a triangular shape resembling some sort of shield. It has a dark reddish brown color and two powerful hindlegs armed with several spines.

The Platine shield harvestman is found in several localities of Argentina and Uruguay, but especially in forested areas around the La Plata River and its tributaries. As usually among gonyleptid harvestmen, the Platine shield harvestman is dependent on environments with a considerable degree of humidity.

Different from most arachnids, harvestmen are usually omnivorous scavengers, feeding on dead animal and plant material, and the Platine shield harvestman is not different. In predator-prey relationships, they are usually the prey of other animals, especially spiders, such as wolf spiders that share the same habitat. When facing a large spider that is about to hunt it, the Platine shield harvestman can use a series of defense mechanisms. One of the simplest ways to avoid being eaten is remaining motionless or playing dead, a behavior called thanatosis. When facing an apparently dead harvestman, a wolf spider usually ignores it completely, as if it wasn’t even there. When this is not enough to stop the attack, the harvestman can use additional strategies, such as “showing its butt” to the spider by lifting its abdomen toward the predator and sometimes kicking the spider with its hind legs. Another common defense mechanism in harvestmen is releasing chemicals with a strong and repulsive scent but the Platine shield harvestman does not seem to use it often, at least not against spiders.

Little is known about the natural history of the Platine shield harvestman or of any of its close relatives. As I said several times before, we need more people studying the small creatures that live all around us.

– – –

Like us on Facebook!

Follow us on Twitter!

– – –

References:

Costa LE, Guerrero EL (2011) Geographical distribution of Discocyrtus prospicuus (Arachnida: Opiliones: Gonyleptidae): Is there a pattern? Zootaxa 2043: 1–24.

Fernandes NS, Stanley E, Costa FG, Toscano-Gadea CA, Willemart RH (2017) Chemical sex recognition in the harvestman Discocyrtus prospicuus (Arachnida: Opiliones). Acta Ethologica 20(3): 215–221. doi: 10.1007/s10211-017-0264-5

Segalerba A, Toscano-Gadea CA (2016) Description of the Defensive Behaviour of Four Neotropical Harvestmen (Laniatores: Gonyleptidae) Against a Synchronic and Sympatric Wolf Spider (Araneae: Lycosidae). Arachnology 17(1): 52–58. doi:10.13156/arac.2006.17.1.52 

– – –

*Creative Commons License This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

Leave a comment

Filed under Arachnids, Friday Fellow

Whose Wednesday: Émile Blanchard

by Piter Kehoma Boll

Today we celebrate the birthday of a French zoologist and rival of Darwin.

Charles Émile Blanchard was born in Paris on 6 March 1819, the son of the painter Émile-Théophile Blanchard. Due to his father’s interest in nature, Blanchard started to engage in the study of natural history since an early age. When he was 14, in 1833, the naturalist Jean Victoire Audouin allowed him access to the laboratory of the Muséum National d’Histoire Naturelle. Five years later, in 1838, he became a technician in the museum and, in 1841, was promoted to assistant-naturalist.

Soon after that, Blanchard went on a marine zoology expedition to Sicily with the zoologists Henri Milne-Edwards and Jean Louis Armand de Quatrefages de Breau.

In 1845, Blanchard published a book entitled Histoire des Insects (History of the Insects). About a decade later, from 1854 to 1856, he published his work Zoologie Agricole (Agricultural Zoology), which is a remarkable work, illustrated by his father, which presents in great details how harmful species damage crops. Between 1852 and 1864 he also published an atlas of the anatomy of the vertebrates.

From about 1860 on, Blanchard started to gradually lose sight. However, this did not discourage him to continue his work.

In 1862, he received the chair of crustaceans, arachnids and insects of the Muséum and was elected a member of the French Academy of Sciences. By this time, he started to gradually restrict the access by amateurs to the collections of the museum, which led the overall activity of the museum to decline and the collections to become dispersed.

In 1870, with the death of August Duméril, the chair of reptiles and fish of the Muséum was left vacant and Blanchard was hoping to receive it due to his atlas of the anatomy of vertebrates, but the chair was given to Léon Vaillant instead.

Blanchard in his late years.

Blanchard was openly against Darwinism and stated that Darwin’s ideas on evolution were false and unoriginal. In 1870, Darwin was nominated by Quatrefages and Milne-Edwards to be a corresponding member of the French Academy of Sciences. This was strongly opposed by Blanchard and others, which led Darwin to lose the election by a narrow margin.

Blanchard became completely blind in 1890, but continued with the chair of the crustaceans, arachnids and insects until 1894. He died on 11 February 1900, aged 84.

– – –

References:

Global Ant Project. Charles Émile Blanchard (1819–1900). Available at < https://archive.is/20120724124107/http://gap.entclub.org/taxonomists/Blanchard/index.html >. Access on 5 March 2019.

Wikipédia (in French). Émile Blanchard. Available at < https://fr.wikipedia.org/wiki/%C3%89mile_Blanchard >. Access on 5 March 2019.

Leave a comment

Filed under Biographies

New Species: February 2019

by Piter Kehoma Boll

Here is a list of species described this month. It certainly does not include all described species. Most information comes from the journals Mycokeys, Phytokeys, Zookeys, Phytotaxa, Zootaxa, International Journal of Systematic and Evolutionary Microbiology, and Systematic and Applied Microbiology, as well as journals restricted to certain taxa.

Bacteria

Archaea

SARs

Senyuia granitica is a new flowering plant from Malaysia. Credits to Kiew & Lau, 2019.*

Plants

Amoebozoans

Tuber pulchrosporum is a new truffle from the Balkans. Credits to Polemis et al., 2019.*

Fungi

Tremella cheejenii (A), T. erythrina (B) and T. salmonea (C) are three new basidiomycetes from China. Credits to Zhao et al., 2019.*

Choanoflagellates

Sponges

Neopetrosia sigmafera is a new sponge from the Caribbean. Credits to Vicente et al., 2019.*

Cnidarians

Flatworms

Acanthocephalans

Vermatus biperforatus is a new sessile gastropod with an unusual two-hole shell dome covering the shell opening. Credits to Bieler et al., 2019.*

Mollusks

Annelids

Kinorhynchs

Nematodes

Arachnids

Myriapods

Solinca aulix is a new crab from Ecuador and Peru. Credits to Colavite et al., 2019.*

Crustaceans

Coecobrya sirindhornae, a new cave springtail from Thailand. Credits to Jantarit et al., 2019.*

Hexapods

Oxynoemacheilus cemali, a new fish from Turkey. Credits to Turan et al., 2019.

Ray-finned fishes

Phrynobactrachus bibita is a new frog from Ethiopia. Credits to Goutte et al. 2019.*

Amphibians

Pelodiscus variegatus is a new turtle from Indochina. Credits to Farkas et al., 2019.*

Reptiles

– – –

*Creative Commons License This work is licensed under a Creative Commons Attribution 4.0 International License.

Leave a comment

Filed under Systematics, taxonomy

Friday Fellow: Club-like Tuning Fork

by Piter Kehoma Boll

If you are walking around in the woods sometime after heavy rains, you may see clusters of small yellow to orange slick finger-like projections coming out of the barkless wood of dead trees such as oaks and other hardwoods. These little structures are the fruiting bodies of Calocera cornea, also known as the club-like tuning fork.

Calocera cornea growing on decaying oak wood. Photo by Ashley Duval.*

The club-like tuning fork may look at first like a club fungus, but those are distant relatives. It actually belongs to a group called Dacrymycetes, which constitutes one of the many groups commonly knowns as jelly fungi. The finger-like fruiting bodies, called basidiocarps, are very variable in shape, although usually not branched, and contain several Y-shaped basidia, each carrying two spores.

With a worldwide distribution, the club-like tuning fork grows on decaying wood of several trees, both angiosperms and gymnosperms, but is more fond of hardwoods such as the oak, so it is more commonly found in temperate forests in places such as North America and Eurasia. Its hyphae never grow very deep, being restricted to the more superficial layers of wood, and are very narrow, about 1µm in diameter only, and grow parallel to the long axis of the dead cells of the wood.

Club-like tuning fork growing together with other wood-decaying fungi. Photo by Christian Schwarz.*

Although usually not a species of economic concern, some strains of the club-like tuning fork may cause considerable decay in wood objects that have not been properly treated to avoid fungus growth.

Recently, the genome of Calocera cornea has been sequenced as part of a project that is trying to determine the origins of the ability of basidiomycetes to decompose lignocellulose, the main component of the cell walls of woody plants.

– – –

Like us on Facebook!

Follow us on Twitter!

– – –

References:

Kennedy LL (1972) Basidiocarp development in Calocera cornea. Canadian Journal of Botany 50(3): 413–417. doi: 10.1139/b72-060

McNabb RFR (1965) Taxonomic studies in the Dacrymycetaceae. II. Calocera (Fries) Fries. New Zealand Journal of Botany 3(1): 31–58. doi: 10.1080/0028825X.1965.10428712

MushroomExpert.Com. Calocera cornea. Available at < https://www.mushroomexpert.com/calocera_cornea.html >. Access on 10 February 2019.

Nagy LG, Riley R, Tritt A, Adam C, Daum C, Floudas D, Sun H, Yadav JS, Pangilinan J, Larsson KH, Matsuura K, Barry K, Labutti K, Kuo R, Ohm RA, Bhattacharya SS, Shirouzu T, Yoshinaga Y, Martin FM, Grigoriev IV, Hibbett DS (2016) Comparative Genomics of Early-Diverging Mushroom-Forming Fungi Provides Insights into the Origins of Lignocellulose Decay Capabilities. Molecular Biology and Evolution 33(4):959-70. doi: 10.1093/molbev/msv337

– – –

*Creative Commons License This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

Leave a comment

Filed under Friday Fellow, Fungi