A group of approximately 100 researchers, lecturers, and students at the University of the Free State (UFS) recently celebrated Gregor Mendel’s 200th anniversary with a guest lecture presented by Dr Frank Zachos, scientist, author, and curator of mammals at the Natural History Museum in Vienna, one of the world’s largest natural history museums in the world with its more than 30 million specimens. 

Several researchers from different disciplines, including conservation genetics (Prof Paul Grobler), forensic genetics (Dr Karen Ehlers), human genetics (Dr Gerda Marx), plant genomics (Dr Mathabatha Maleka), and fungal systematics (Dr Marieka Gryzenhout) also did presentations on the influence and application of Mendel’s work on their respective fields at this event hosted by the Department of Genetics on the UFS Bloemfontein Campus. 

In Dr Zachos’ lecture titled, From peas to population genetics, he provided facts about Mendel’s history, his work, as well as some milestones in genetics after his death. 

Mendel, an Austrian by birth, studied a number of sciences, including physics, botany, meteorology, and mathematics. Setting out to study hybridisation in particular (which could result in the origin of new species) and not inheritance in general, the pea plant experiments he conducted between 1856 and 1863 established many of the rules of heredity, which are now being referred to as the laws of Mendelian inheritance. He published his work (Experiments in Plant Hybridisation) in 1866, seven years after Charles Darwin, the father of evolution, published his work.

Dr Zachos also spent a part of his presentation in describing the engagement between Mendel and Darwin. He found that Darwin had made a point of not reading Mendel’s work. However, Mendel studied Darwin’s work extensively – many notes and comments were found in the margins of the copies Mendel had of Darwin’s books.

Mendel’s work, however, was at first ignored by the scientific community. Nevertheless, he believed ‘Meine Zeit wird noch kommen’ (My time will come). It was after his death, when he gained recognition as the founder of the modern science of genetics, that his work was appreciated. 

The results of Mendel’s studies are the foundation of what we now know as genetics. Mendel’s discoveries were followed by a number of milestones in genetics that he could not have foreseen at the time. Dr Zachos pointed out, for instance, the chromosome theory of inheritance (1902) as well as the discovery of DNA double helix (1953).

Dr Zachos, working in Vienna where Mendel spent much of his time, was the ideal person to deliver this lecture. Besides his work at the museum, Dr Zachos is an Affiliated Professor in the Department of Genetics. Some of his research interests include the population and conservation genetics of mammals and birds. He has delivered more than 100 articles on this topic, with some of his more recent work published in Mammals of Europe: past, present, and future (2020) and Species problems and beyond: Contemporary issues in philosophy and practice (2022). He also has a keen interest in biodiversity, saying that three of the world’s biodiversity hotspots are in South Africa. He conducted some of this research on South African animals, including the blue antelope, the gemsbok, and the impala. 

He believes that a biodiversity crisis exists and that many species are threatened by extinction. “Conservation biology is a timely discipline, and genetics is at the core of it,” said Dr Zachos. 

Another danger is inbreeding. This not only results in a loss of genetic diversity, but also increases the risk of extinction as it lowers reproduction. Dr Zachos was referring to the North American puma, which became sterile due to inbreeding.

“It is very important that people know the basics of genetics. Genetic literacy is of the utmost importance,” said Dr Zachos.