Everything about Gregor Johann Mendel totally explained
Gregor Johann Mendel (
July 20,
1822 –
January 6,
1884) was an
Augustinian priest and
scientist, and is often called the father of
genetics for his study of the
inheritance of
traits in
pea plants. Mendel showed that the inheritance of traits follows particular
laws, which were later named after him. The significance of Mendel's work wasn't recognized until the turn of the
20th century. Its rediscovery prompted the foundation of the discipline of genetics.
Biography
Mendel was born into a
German-speaking family in Heinzendorf,
Austrian Silesia,
Austrian Empire (now
Hynčice,
Czech Republic), and was baptized two days later. He was the son of Anton and Rosine Mendel, and had one older sister and one younger. During his childhood, Mendel worked as a gardener, studied
beekeeping, and as a young man attended the
Philosophical Institute in
Olomouc in 1840-1843. Upon recommendation of his
physics teacher Friedrich Franz, he entered the
Augustinian Abbey of St. Thomas in Brno in 1843. Born Johann Mendel, he took the name Gregor upon entering
monastic life. In 1851 he was sent to the
University of Vienna to study, returning to his abbey in 1853 as a teacher, principally of physics.
Gregor Mendel, who is known as the "father of modern genetics", was inspired by both his professors at university and his colleagues at the monastery to study variation in plants, and he conducted his study in the monastery's garden. Between 1856 and 1863 Mendel cultivated and tested some 29,000
pea plants (for example
Pisum sativum). This study showed that one in four pea plants had
purebred recessive alleles, two out of four were
hybrid and one out of four were purebred
dominant. His experiments brought forth two generalizations which later became known as Mendel's Laws of Inheritance.
Mendel read his paper, "
Experiments on Plant Hybridization", at two meetings of the
Natural History Society of Brünn in
Moravia in 1865. When Mendel's paper was published in 1866 in
Proceedings of the Natural History Society of Brünn, it had little impact and was cited about three times over the next thirty-five years. His paper was criticized at the time, but is now considered a seminal work.
After Mendel completed his work with peas, he turned to experimenting with honeybees, in order to extend his work to animals. He produced a hybrid strain (so vicious they were destroyed), but failed to generate a clear picture of their heredity because of the difficulties in controlling mating behaviours of queen bees. He also described novel plant
species, and these are denoted with the
botanical author abbreviation "Mendel".
Elevated as
abbot in 1868, his scientific work largely ended as Mendel became consumed with his increased administrative responsibilities, especially a dispute with the civil government over their attempt to impose special taxes on religious institutions.
At first Mendel's work was rejected, and it wasn't widely accepted until after he died. The common belief at the time was that
pangenes were responsible for inheritance. Even
Darwin's theory of
evolution used pangenesis instead of Mendel's model of inheritance. The
modern synthesis uses Mendelian genetics.
Mendel died on
January 6,
1884, at age 61, in
Brno,
Austria-Hungary (now
Czech Republic), from chronic
nephritis. Czech composer
Leoš Janáček played the organ at his funeral. After his death, the following abbot burned all papers in Mendel's collection.
Rediscovery of Mendel's work
It wasn't until the early
20th century that the importance of his ideas was realized. In 1900, his work was rediscovered by
Hugo de Vries and
Carl Correns. Though
Erich von Tschermak was originally also credited with rediscovery, this is no longer accepted because he didn't understand Mendel's laws. Mendel's results were quickly replicated, and genetic linkage quickly worked out. Biologists flocked to the theory, even though it wasn't yet applicable to many phenomena, it sought to give a
genotype understanding of heredity which they felt was lacking in previous studies of heredity which focused on
phenotypic approaches. Most prominent of these latter approaches was the
biometric school of
Karl Pearson and
W.F.R. Weldon, which was based heavily on statistical studies of phenotype variation. The strongest opposition to this school came from
William Bateson, who perhaps did the most in the early days of publicising the benefits of Mendel's theory (the word "
genetics", and much of the discipline's other terminology, originated with Bateson). This debate between the biometricians and the Mendelians was extremely vigorous in the first two decades of the twentieth century, with the biometricians claiming statistical and mathematical rigor, whereas the Mendelians claimed a better understanding of biology. In the end, the two approaches were combined as
the modern synthesis of evolutionary biology, especially by work conducted by
R. A. Fisher as early as 1918.
Mendel's experimental results have later been the object of considerable dispute. Fisher analyzed the results of the F2 (second filial) ratio and found them to be implausibly close to the exact ratio of 3 to 1. Only a few would accuse Mendel of
scientific malpractice or call it a
scientific fraud — reproduction of his experiments has demonstrated the validity of his hypothesis — however, the results have continued to be a mystery for many, though it's often cited as an example of
confirmation bias. This might arise if he detected an approximate 3 to 1 ratio early in his experiments with a small sample size, and continued collecting more data until the results conformed more nearly to an exact ratio. It is sometimes suggested that he may have censored his results, and that his seven traits each occur on a separate chromosome pair, an extremely unlikely occurrence if they were chosen at random. In fact, the genes Mendel studied occurred in only four linkage groups, and only one gene pair (out of 21 possible) is close enough to show
segregation distortion; this isn't a pair that Mendel studied.
Further Information
Get more info on 'Gregor Johann Mendel'.
|
External Link Exchanges
Do you know how hard it is to get a link from a large encyclopaedia? Well we're different and will prove it. To get a link from us just add the following HTML to your site on a relevant page:
<a href="http://gregor_mendel.totallyexplained.com">Gregor Mendel Totally Explained</a>
Then simply click through this link from your web page. Our crawlers will verify your link, extract the title of your web page and instantly add a link back to it. If you like you can remove the words Totally Explained and embed the link in article text.
As long as your link remains in place, we'll keep our link to you right here. Please play fair - our crawlers are watching. Your site must be closely related to this one's topic. Any kind of spamming, dubious practises or removing the link will result in your link from us being dropped and, potentially, your whole site being banned. |