Evolution Warning: You are not logged in. Your IP address will be publicly visible if you make any edits. If you log in or create an account, your edits will be attributed to your username, along with other benefits.Anti-spam check. Do not fill this in! === Pangenesis and heredity === The mechanisms of reproductive heritability and the origin of new traits remained a mystery. Towards this end, Darwin developed his provisional theory of [[pangenesis]].<ref name="Liu09">{{cite journal |author1=Y. -S. Liu |author2=X. M. Zhou |author3=M. X. Zhi |author4=X. J. Li |author5=Q. L. Wang |s2cid=19919317 |date=September 2009 |title=Darwin's contributions to genetics |journal=Journal of Applied Genetics |volume=50 |issue=3 |pages=177β184 |doi=10.1007/BF03195671 |issn=1234-1983 |pmid=19638672}}</ref> In 1865, [[Gregor Mendel]] reported that traits were inherited in a predictable manner through the [[Mendelian inheritance#Law of Independent Assortment|independent assortment]] and segregation of elements (later known as genes). Mendel's laws of inheritance eventually supplanted most of Darwin's pangenesis theory.<ref name="Weiling">{{cite journal |last=Weiling |first=Franz |date=July 1991 |title=Historical study: Johann Gregor Mendel 1822β1884 |journal=[[American Journal of Medical Genetics]] |volume=40 |issue=1 |pages=1β25; discussion 26 |doi=10.1002/ajmg.1320400103 |pmid=1887835}}</ref> [[August Weismann]] made the important distinction between [[germ cell]]s that give rise to [[gamete]]s (such as [[sperm]] and [[egg cell]]s) and the [[somatic cell]]s of the body, demonstrating that heredity passes through the germ line only. [[Hugo de Vries]] connected Darwin's pangenesis theory to Weismann's germ/soma cell distinction and proposed that Darwin's pangenes were concentrated in the [[cell nucleus]] and when expressed they could move into the [[cytoplasm]] to change the [[Cell (biology)|cell]]'s structure. De Vries was also one of the researchers who made Mendel's work well known, believing that Mendelian traits corresponded to the transfer of heritable variations along the germline.<ref name="Wright84">{{harvnb|Wright|1984|p=480}}</ref> To explain how new variants originate, de Vries developed [[Mutationism|a mutation theory]] that led to a temporary rift between those who accepted Darwinian evolution and biometricians who allied with de Vries.<ref>{{harvnb|Provine|1971}}</ref><ref>{{cite journal |last1=Stamhuis |first1=Ida H. |last2=Meijer |first2=Onno G. |last3=Zevenhuizen |first3=Erik J. A. |date=June 1999 |title=Hugo de Vries on Heredity, 1889β1903: Statistics, Mendelian Laws, Pangenes, Mutations |url=https://archive.org/details/sim_isis_1999-06_90_2/page/238 |volume=90 |issue=2 |pages=238β267 |journal=[[Isis (journal)|Isis]] |doi=10.1086/384323 |jstor=237050 |pmid=10439561|s2cid=20200394 }}</ref> In the 1930s, pioneers in the field of [[population genetics]], such as [[Ronald Fisher]], [[Sewall Wright]] and [[J. B. S. Haldane]] set the foundations of evolution onto a robust statistical philosophy. The false contradiction between Darwin's theory, genetic mutations, and [[Mendelian inheritance]] was thus reconciled.{{sfn|Bowler|1989|pp=307β318}} Summary: Please note that all contributions to Christianpedia may be edited, altered, or removed by other contributors. If you do not want your writing to be edited mercilessly, then do not submit it here. You are also promising us that you wrote this yourself, or copied it from a public domain or similar free resource (see Christianpedia:Copyrights for details). Do not submit copyrighted work without permission! Cancel Editing help (opens in new window) Discuss this page