OBITUARY

In memoriam: Hermann Hartwig, 1910–2012

Uwe Kierdorf & Horst Kierdorf

Published online: 27 February 2014# Springer-Verlag Berlin Heidelberg 2014

Antler biology mourns the loss of its nestor, whose work laidthe foundations for our current understanding of the develop-mental biology of antler growth and regeneration. After a longlife in science, Professor Dr. Hermann Hartwig passed awayon 9 September 2012 at the age of 102.

Hermann Hartwig was born on 1 January 1910 inBielefeld. He attended school at his hometown and in 1929qualified for university entrance. Subsequently, he was admit-ted to the University of Greifswald, where he studied zoology,botany, and geology for his first two semesters. He thencontinued his studies at the University of Göttingen, wherehe worked in the laboratory of Alfred Kühn. Hartwig’s doc-toral dissertation concerned the effect of temperature on thethyroid gland of larval fire salamanders and their develop-ment. His oral doctoral exam took place on 6 May 1935. Thethesis was published in 1936 (Roux’ Arch EntwicklungsmechOrg 134, 562–587) and Hermann Hartwig’s doctoral diplomatherefore dates from that year.

After his oral exam, Hermann Hartwig moved to theUniversity of Freiburg where, funded by the RockefellerFoundation, he worked in the University’s ChemicalLaboratory that was headed by F. Gottwalt Fischer. Fischercollaborated closely with the director of the ZoologicalInstitute at the University of Freiburg, Hans Spemann(Nobel laureate of 1935), on the chemical nature of the induc-tive agents operating during early amphibian development.Hartwig’s work was focused on oxidation/reduction activitiesand oxygen consumption in amphibian embryos. He receiveda friendly welcome into Spemann’s group and the contact withSpemann, like that with his teacher Kühn, had a decisiveimpact on his scientific thinking. Hermann Hartwig’s scien-tific worldview was that of an experimental zoologist, and his

firm belief was that the right way to solve a scientific questionwas to design and perform the appropriate experiment.

In 1937, Hermann Hartwig moved to Cologne Universityto take up a position as assistant lecturer at the ZoologicalInstitute. Here, he cooperated mainly with his friend EckhardRotmann, a former graduate student of Spemann. Together,they worked on neoteny in newts. During this period, Hartwigalso studied the local action of thyroxine in amphibian meta-morphosis. He was the first to demonstrate that local meta-morphic effects could be triggered by implantation ofthyroxine-soaked agar beads.

All further plans for an academic career became futile withthe outbreak ofWorldWar II. Hermann Hartwig served first asan infantryman and later as member of a bacteriological lab ofthe Army Medical Service. After the war, he returned into aheavily destroyed Cologne. His foremost activities during theearly postwar period were to participate in rebuilding theZoological Institute and in restarting teaching activities. In1951, he earned his habilitation and thereafter became a“Dozent” and later a professor. He lectured mainly in thefields of animal embryology and developmental biology, butalso in ethology. In the latter field, he was strongly influencedby the works of Konrad Lorenz.

In the early 1960s, Hermann Hartwig started with the workfor which he became famous, namely the developmentalbiology of pedicle and first antler growth in deer. His exper-iments, which used the classical techniques of tissue deletionand transplantation, were performed on roe deer fawns thatHartwig kept in his private garden, cared for by him and hisfamily.

In a first series of experiments, Hartwig demonstrated thatautologous transplantation of the skin overlying the prospec-tive pedicle site of the frontal bone to the thigh region did notresult in ectopic antler growth. It was further shown thatreplacement of the skin from the prospective pedicle site withskin growing in from surrounding scalp areas did not prevent

U. Kierdorf :H. Kierdorf (*)University of Hildesheim, Hildesheim, Germanye-mail: kierdorf@uni-hildesheim.de

Eur J Wildl Res (2014) 60:159–160DOI 10.1007/s10344-014-0802-7

orthotopic pedicle and antler growth. In contrast, removal ofthe periosteum from the prospective pedicle site inhibitedpedicle and antler growth. This indicated that in deer, theperiosteum of the prospective pedicle site, not the skin, isresponsible for the initiation of cranial appendage growth. In asecond series of experiments, the periosteum from the prospec-tive pedicle site was grafted to other areas of the frontal orparietal bones, which caused ectopic pedicle and antler growthfrom these locations. Finally, he demonstrated that autologoustransplantation of the periosteum from the prospective pediclesite to the metacarpal region likewise induced ectopic antlergrowth. The bony structures that formed at the metacarpus wereshort and abnormally shaped, but covered with typical velvetskin during growth and replaced in synchrony with the antlergrowing from the unoperated site. Hartwig’s seminal paper onthese experiments was published, with J. Schrudde as coauthor,in the Zeitschrift für Jagdwissenschaft (20, 1974, 1–13).

Hermann Hartwig’s discovery of what is now known as the“antlerogenic periosteum” and its decisive role for pedicle(and first antler) formation constitutes a milestone in thehistory of antler science and opened up a whole new field ofresearch. The first to continue this line of investigation was R.J. Goss, who confirmed and extended Hartwig’s findings in asecond species, the fallow deer. Further studies then addressedthe specific properties of the antlerogenic periosteum in moredetail. These studies led to the currently held view that theformation of pedicles and primary antlers is dependent onstem/progenitor cells located in the cambium layer of theantlerogenic periosteum, and that annual antler regenerationdepends on the activation of stem/progenitor cells in thepedicle periosteum, derived from those of the antlerogenicperiosteum.

Upon retirement, Hartwig discontinued his experimentalstudies, but retained a keen interest in all questions related toantler growth and morphogenesis. Following the dictum“pathologia physiologiam illustrat,” he intensified his long-standing interest in antler malformations in an attempt toachieve a better understanding of normal antler growth bystudying specific abnormalities. His occupation with abnor-mal antlers resulted in some very thoughtful analyses of antleranomalies in roe deer. Given the focus of his scientific inter-ests, it does not come as a surprise that Hermann Hartwig’stwo last scientific papers, published at age 79 (Z Jagdwiss 35,1989, 130–136 and 184–191), concerned questions of pedicleand antler growth. After discontinuing his own research ac-tivities, he followed the progress in antler research with greatinterest for more than another 20 years.

His former undergraduate and graduate students will re-member Hermann Hartwig as an exceptional academic teach-er. He was known for his attention to precision in exposition,

both in his lectures and his writings. He also expected preci-sion from his students, and frequently his remarks and correc-tions on a draft paper were much longer than the draft itself.He was convinced that the search for the right word wasalways a worthwhile enterprise, and often referred to MarkTwain’s sentence that “the difference between the almost rightword and the right word is really a large matter—it is thedifference between the lightning bug and the lightning.”Hermann Hartwig was thus certainly not the “easiest” tutorthat one could choose; however, he was always a very en-gaged one with a strong interest in promoting the intellectualadvancement and scientific progress of his students. Withmany of them, he established a life-long contact, and hefollowed their careers with great interest and sympathy.

A pervading theme of Hermann Hartwig’s life was his lovefor nature and animals. He kept dachshunds for a long time,his four-legged companion accompanying him each day towork in the University. Throughout his life, Hermann Hartwigwas also a devoted student of animal behavior. Thus, thenalready in his nineties, he could proudly demonstrate to visi-tors a wild mouse from his garden that he had trained withgreat patience to climb up the rainwater pipe, proceed throughthe open living-roomwindow, and take a sunflower seed fromhis hand before returning into the garden. Since his youth,Hartwig had also been a hunter for whom hunting was a wayto come into close contact with nature and to attain a betterunderstanding of wild animals and their behavior.

Herrmann Hartwig was a person of great composure and avery modest man, who never strived for public appreciationand thoroughly disliked all fuss about his person. He lived asecluded life, mostly staying in contact with his friends andcolleagues by exchange of letters. His mastery in writing madeit a great pleasure to receive a letter from him, either written inhis neat and clear handwriting or typed on his old mechanicaltypewriter, as he never personally entered the computer age.Those forming the “inner circle” enjoyed being invited to visithim at his home and to relish his great hospitality. Theseafternoon meetings with like-minded people followed an un-changed course over decades and were mostly but not exclu-sively devoted to the discussion of biological topics of mutualinterest. You could give Hermann Hartwig a great pleasure bybringing along an interesting biological specimen, like a mal-formed antler or an anomalous dentition, or by being accom-panied by your dog. On these occasions, he also demonstratedhis great talents as a narrator. He was full of anecdotes fromhis long life and presented them with his typical dry wit.Hermann Hartwig not only leaves an important scientificlegacy, but will also be remembered as an upright and sym-pathetic academic teacher and colleague, and a true professorin the literal meaning of the word.

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