Berthold Hatschek (3 April 1854 in

Skrbeň Skrbeň is a municipality and village in Olomouc District in the Olomouc Region of the Czech Republic. It has about 1,100 inhabitants. Skrbeň lies approximately north-west of Olomouc and east of Prague. Demographics Notable people *Berthold ...

– 18 January 1941 in

Vienna Vienna ( ; ; ) is the capital city, capital, List of largest cities in Austria, most populous city, and one of Federal states of Austria, nine federal states of Austria. It is Austria's primate city, with just over two million inhabitants. ...

) was an Austrian

zoologist Zoology ( , ) is the scientific study of animals. Its studies include the structure, embryology, classification, habits, and distribution of all animals, both living and extinct, and how they interact with their ecosystems. Zoology is one ...

remembered for

embryological Embryology (from Greek ἔμβρυον, ''embryon'', "the unborn, embryo"; and -λογία, ''-logia'') is the branch of animal biology that studies the prenatal development of gametes (sex cells), fertilization, and development of embryos an ...

and morphological studies of

invertebrates Invertebrates are animals that neither develop nor retain a vertebral column (commonly known as a ''spine'' or ''backbone''), which evolved from the notochord. It is a paraphyletic grouping including all animals excluding the chordate subphylum ...

Life

Berthold Hatschek studied zoology in

under Carl Claus (1835–1899), and in

Leipzig Leipzig (, ; ; Upper Saxon: ; ) is the most populous city in the States of Germany, German state of Saxony. The city has a population of 628,718 inhabitants as of 2023. It is the List of cities in Germany by population, eighth-largest city in Ge ...

with

Rudolf Leuckart Karl Georg Friedrich Rudolf Leuckart (7 October 1822 – 22 February 1898) was a German zoologist born in Helmstedt. He was a pioneer of parasitology research and was widely known for developing a series of illustrated wall charts for use in zo ...

(1822–1898). He gained his doctorate at the

University of Leipzig Leipzig University (), in Leipzig in Saxony, Germany, is one of the world's oldest universities and the second-oldest university (by consecutive years of existence) in Germany. The university was founded on 2 December 1409 by Frederick I, Electo ...

with a dissertation titled ''Beiträge zur Entwicklungsgeschichte der Lepidopteren''. Hatschek was deeply influenced by the works of

Ernst Haeckel Ernst Heinrich Philipp August Haeckel (; ; 16 February 1834 – 9 August 1919) was a German zoologist, natural history, naturalist, eugenics, eugenicist, Philosophy, philosopher, physician, professor, marine biology, marine biologist and artist ...

(1834–1919). In 1885 he was appointed professor of zoology at

Charles University in Prague Charles University (CUNI; , UK; ; ), or historically as the University of Prague (), is the largest university in the Czech Republic. It is one of the oldest universities in the world in continuous operation, the oldest university north of the ...

, and from 1896 was a professor and director of the second zoological institute at the

University of Vienna The University of Vienna (, ) is a public university, public research university in Vienna, Austria. Founded by Rudolf IV, Duke of Austria, Duke Rudolph IV in 1365, it is the oldest university in the German-speaking world and among the largest ...

. Hatschek suffered from severe depression, which greatly affected his work in the latter stages of his life. Hatschek is remembered for his "trochophore theory", in which he explains the

trochophore A trochophore () is a type of free-swimming planktonic marine larva with several bands of cilia. By moving their cilia rapidly, they make a water eddy to control their movement, and to bring their food closer in order to capture it more easily. ...

to be the larval form of a hypothetical organism- the "trochozoon" (which in adult form corresponded to a trochophore-like

rotifer The rotifers (, from Latin 'wheel' and 'bearing'), sometimes called wheel animals or wheel animalcules, make up a phylum (Rotifera ) of microscopic and near-microscopic Coelom#Pseudocoelomates, pseudocoelomate animals. They were first describ ...

, and was the suggested common ancestor of almost all

bilaterian Bilateria () is a large clade of animals characterised by bilateral symmetry during embryonic development. This means their body plans are laid around a longitudinal axis with a front (or "head") and a rear (or "tail") end, as well as a left–r ...

animal lifeforms). In 1888 he split

Frey Freyr (Old Norse: 'Lord'), sometimes anglicized as Frey, is a widely attested god in Norse mythology, associated with kingship, fertility, peace, prosperity, fair weather, and good harvest. Freyr, sometimes referred to as Yngvi-Freyr, was especi ...

and Leuckart's

Coelenterata Coelenterata is a term encompassing the animal phyla Cnidaria (corals, true jellies, sea anemones, sea pens, and their relatives) and Ctenophora (comb jellies). The name comes , referring to the hollow body cavity common to these two phyla. Th ...

into three phyla: Spongiaria,

Cnidaria Cnidaria ( ) is a phylum under kingdom Animalia containing over 11,000 species of aquatic invertebrates found both in fresh water, freshwater and marine environments (predominantly the latter), including jellyfish, hydroid (zoology), hydroids, ...

and

Ctenophora Ctenophora (; : ctenophore ) is a phylum of marine invertebrates, commonly known as comb jellies, that inhabit sea waters worldwide. They are notable for the groups of cilia they use for swimming (commonly referred to as "combs"), and they are ...

. From his research of

lancelet The lancelets ( ), also known as amphioxi (: amphioxus ), consist of 32 described species of somewhat fish-like benthic filter feeding chordates in the subphylum Cephalochordata, class Leptocardii, and family Branchiostomatidae. Lancelets dive ...

s (amphioxus), the anatomical terms " Hatschek's pit" and "Hatschek's nephridium" are derived.

Selected writings

''Studien über Entwicklungsgeschichte der Anneliden. Ein Beitrag zur Morphologie der Bilaterien''
1878.
''Studien über entwicklung des Amphioxus''
1881.
''Lehrbuch der Zoologie : eine morphologische Übersicht des Thierreiches zur Einführung in das Studium dieser Wissenschaft''
1888.
"The Amphioxus and its development", translated into English, 1893
* ''Das acromerit des Amphioxus'', 1906. * ''Das neue Zoologische System'', 1911.WorldCat Identities
(bibliography)

References

{{DEFAULTSORT:Hatschek, Berthold 1941 deaths 1854 births Embryologists Austrian zoologists Moravian-German people Leipzig University alumni Academic staff of the University of Vienna Academic staff of Charles University People from Olomouc District Zoologists from Austria-Hungary