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Although some leading scientists in the late nineteenth century considered religion to be an impediment to progress in science, the life of the monk Gregor Mendel serves as an important counter-example. The fact that a monk initiated one of the greatest advances in biology demonstrates the poverty of the notion of there being a perpetual war between science and religion. In Mendel's case, rather than hindering science, religious institutions promoted scientific knowledge, experimentation, and progress.

Early life and influences

On July 22, 1822, Mendel was born in the village of Heinzendorf (now Hyncice) in northern Moravia (in the present-day Czech Republic), a part of the Austrian Empire that was culturally German. Mendel was originally named Johann, but took the name Gregor in 1843 upon entering the Augustinian order of the Roman Catholic Church. His father was a peasant farmer with a keen interest in improving agriculture. A priest in his community, Father Schreiber, used his knowledge of fruit trees to help his parishioners practically. He studied the latest techniques for improving fruit yields, practiced artificial fertilization, and distributed grafts to community members, including the Mendel family.

Mendel's intellectual abilities were recognized early in his life, and his family sent him to school first in Leipnik (Lipnik) and then to Gymnasium in Troppau (Opava). After graduating from Gymnasium, he attended a two-year course of study at the Philosophical Institute in Olmütz (Olomouc), which was interrupted for a year due to illness. He graduated from the Philosophical Institute in 1843, having studied religion, philosophy, ethics, mathematics, and physics, in order to prepare for further studies in natural science at a university. While in Olmütz, Mendel had grave financial difficulties because his father was incapacitated from work as a result of an injury, and Mendel had difficulty finding tutoring jobs. His poverty probably brought on his illness and caused him continual travail.

Upon the recommendation of one of his teachers, Mendel entered the Augustinian monastery in Brno in 1843. He had begun contemplating entering the Catholic priesthood about three years earlier, but it is not known how seriously or deeply he felt a religious calling. Mendel's own account of entering the monastery emphasized his need to escape from poverty rather than an inner religious motivation. Mendel also knew that the monastery in Brno would be a hospitable environment for pursuing studies in the natural sciences.

Indeed, the Brno monastery, under the leadership of Abbott F. C. Napp, attracted a number of talented men interested in science. Napp himself studied horticulture and wrote a manual about improving plant varieties. He set up a nursery in the monastery where new plant varieties could be developed. Thus, the monastery provided a very propitious environment for the young Mendel, who was encouraged to teach science in nearby schools. The monastery also allowed him to attend the University of Vienna from 1851 to 1853 to study natural science so he could pass the exam to qualify him to teach in a Gymnasium. Mendel never passed this exam, however.

Although the monastery was a stimulating place for the study of natural science, the religious training and exercise in the Brno monastery seems to have been perfunctory. The bishop of Brno criticized Napp and the monastery for devoting so much attention to science, while neglecting the spiritual dimension of monastic life. Shortly after Mendel arrived, a monk there was stripped of his authority to teach because he was accused of introducing Hegelian and pantheistic doctrines into his scientific writings. Napp tried to defend this monk, but to no avail. Mendel never challenged the Catholic Church or its teachings, but his energies were clearly devoted more to scientific pursuits than to religious ones.

Experiments with peas

From 1854 to 1863 Mendel carried out his pea experiments, which later became famous for laying the groundwork for the modern science of genetics. Because Mendel relied on statistics to analyze the results of his work, his background in physics and mathematics provided him insight in developing these experiments. To perform his experiments, Mendel selected twenty-two varieties of pea plants that bred true (i.e., each was a pure variety that, when crossed with its own variety, always had offspring with the same traits as the parents). Each variety was crossed with another with which it differed in an obvious way, such as seed color, pod shape, position of flowers, or length of stem. For example, he crossed one pea variety that had round seeds with another variety that had angular seeds. In the first generation hybrids Mendel observed that all the offspring had the trait of only one of the parent varieties. The hybrid, between peas with round seeds and those with angular seeds produced all round seeds in the first generation. Mendel called the trait that appeared in the first generation the dominant trait. This demonstrated that hereditary characters did not blend, as many scientists of the time supposed they did, but rather they were discrete factors.

Mendel continued his experiment by self-fertilizing the first generation hybrids. He discovered that both original traits reemerged in a ratio approximating three (for the dominant trait) to one (for the recessive trait). In the case of the round and angular seeds, Mendel's actual data showed 5474 round seeds and 1850 angular seeds in the second generation. Mendel concluded from his experiments that each plant had two hereditary characters. Each parent would pass only one of its characters on to its offspring. These characters segregate randomly, leading to the ratios Mendel found. This explanation is known as Mendel's Law of Independent Assortment.

Mendel published the results of his pea experiments in 1866 in the Proceedings of the Natural Science Society of Brno, but even though some botanists cited his work subsequently, none recognized the full significance of his experiments before 1900. Mendel even corresponded with Karl Nägeli (1817–1891), a prominent botanist, but despite his interest in Mendel's work, Nägeli never realized how important it was. When Mendel died on January 6, 1884, he was almost unknown, though he did express confidence late in his life that his work would be recognized in the future.

Historians still debate the significance of biological evolution for Mendel's work. Charles Darwin (1809–1882) had not yet published his theory of evolution when Mendel began his experiments, but Mendel was already conversant with Charles Lyell's (1797–1875) uniformitarian geology, which had been a formative influence on Darwin. Mendel also studied botany at the University of Vienna under Franz Unger (1800–1870), who embraced a pre-Darwinian evolutionary theory. Mendel was thus fully aware of debates about biological variation and speciation, and he may have hoped that his hybridization experiments would shed light on the evolutionary process.

The rediscovery of Mendel's work in 1900 by three different scientists—Hugo de Vries, Carl Correns, and Erich von Tschermak—occurred in the context of debates over evolution. Biological evolution was widely accepted by European scientists by 1900, but scientists did not have a satisfactory explanation as to how variation occurs or what the mechanisms of heredity are. Mendelian genetics provided new insights about heredity, but also posed new problems for evolutionary theory. De Vries argued that Mendelian genetics provided support for discontinuous variation rather than Darwinian gradualism. On the basis of his misinterpretation of primrose hybridization experiments he thought that mutations—the sudden emergence of new characters—drove the evolutionary process. These new characters were then passed on in Mendelian fashion. Other scientists opposed de Vries's mutation theory and continued arguing for gradual variations. The dispute over gradualism versus discontinuous variation was only settled in the 1930s and 1940s with the integration, known as the neo-Darwinian synthesis, of Darwinian natural selection theory with Mendelian genetics.

Implications for religion

The religious implications of Mendel's theory were minimal, so no significant religious opposition to Mendelian genetics arose. However, in the early twentieth century, many eugenics proponents began using Mendelian genetics to promote various programs to control human heredity, including sterilization, birth control, incarceration, and regulation of marriage certificates. The Roman Catholic Church and some conservative Protestants opposed eugenics, but they did not criticize Mendelian genetics. Rather they rejected eugenics as a misuse of genetics.

Probably the most significant connection between Mendelian genetics and religion was the use of Mendelian genetics by creationists. Many creationists hailed Mendel's theory of heredity as a proof for biological stasis. The variations that Mendel (and de Vries) observed only involved the reshuffling of hereditary characters (genes) that were already present, not the introduction of new traits. They rejected the neo-Darwinian synthesis, which argued that micro-mutations could accumulate to produce speciation.

Mendel's life and the reception of his ideas demonstrates the way that religious communities and individuals in nineteenth and early twentieth-century Europe often nurtured scientific discovery. They were not only open to new scientific ideas, but in some cases actively cultivated them.

See also CREATION SCIENCE; EUGENICS; EVOLUTION; GENETICS

RICHARD C. WEIKART