James Robert Brown

John Robert Burns

Title:
Professor Emeritus of Zoology
Email:
jrburns@gwu.edu

Histology; reproductive biology and comparative morphology of fishes.


Former Research

My research over the years has focused on the reproductive biology of teleost fishes, including both physiological and anatomical studies. More recently I have been concentrating on the morphology of reproductive tissues using microscopical analysis (light and electron microscopy- TEM and SEM). I have been carrying out these analyses principally on inseminating and/or viviparous species within the following orders: Cyprinodontiformes and Beloniformes (Atherinomorpha), and Characiformes and Siluriformes (Ostariophysi). The data thus far have revealed a tremendous diversity in the adaptations correlated with these fascinating reproductive habits. In addition to providing information on the basic reproductive biology of these species, the results are providing morphological characters that are proving useful in hypothesizing possible phylogenetic relationships among these fishes. These projects are being carried out in collaboration with Dr. Stanley H. Weitzman, Curator of Fishes at the National Museum of Natural History, Smithsonian Institution.

Gonad Structure and Sperm Ultrastructure 

The main thrust of my current research involves a detailed study of the histology of the gonads and ultrastructure (using both TEM and SEM) of the spermatozoa of inseminating species within the ostariophysin orders Characiformes and Siluriformes. This work has not only demonstrated the great variety of organ and cell specializations associated with this mode of reproduction, but has also uncovered species and taxa heretofore not known to be inseminated. I am attempting to correlate the unique morphological specializations of the spermatozoa with the hydrodynamic problems of insemination. In addition, this work has already provided morphological characters which have proven invaluable in hypothesizing possible phylogenetic relationships among these taxa (Phylogenetic Systematics).

Basic testis structure has even provided us with a possible shared, derived character (synapomorphy) for the characiform subfamily Glandulocaudinae- a large posterior sperm storage area. Other inseminating characins, such as the one inseminating taxon within the subfamily Cheirodontinae, do not possess such a testicular region. In addition, light microscopy has revealed that certain species release sperm packets, referred to as spermatozeugmata, since they lack any distinct covering. Although most, but not all, of the inseminating species have been shown to have spermatozoa with elongated nuclei, the manner of elongation varies among the different species. In addition, some species possess unique structures (e.g., microtubule arrays) not found in the sperm of externally fertilizing species. Even though this project concentrates on inseminating species, gonads and sperm from representative species of a large number of externally fertilizing taxa are being analyzed as well to provide us with outgroup comparisons.

Secondary Sex Characters

For many of the inseminating species under study, the manner in which the spermatozoa are transferred to the female is unknown. Many species lack clear intromittent organs, so I am also carrying out a histological analysis on the anal regions to see if any structures (palps, etc.) are present in the males which may possibly aid in sperm transfer.

The inseminating characin subfamily Glandulocaudinae is characterized by the presence of glandular tissue associated with modified scales on the caudal peduncle. I am also carrying out a detailed histological study of these caudal glands in order to establish the distribution of the glandular tissue and describe the cellular characteristics. In addition, various other (non-glandulocaudine) inseminating species have been reported to possess similar caudal glands. I will also analyze these species to see if they do indeed possess caudal glands, and if so, how they resemble those found in the Glandulocaudinae.

Several years ago I uncovered a unique structure found only in mature males of the glandulocaudine species, Corynopoma riisei, that was derived from the anterior gills of the first gill arches. These gill glands, which consisted of chambers that opened into the gill cavity, produce a colloidal secretion which we hypothesized may function as a pheromone. Since that time, analyses of other characiform taxa have revealed similar structures in mature males of a wide range of species. We are also carrying out a survey of characiform species to see which ones possess gill glands, as well as a detailed microscopical analysis of the any glands found. This information will hopefully clarify the function of these unique structures, as well as provide useful morphological characters for the phylogenetic analyses.

 

Education

B.S., Brooklyn College: CUNY, NY, 1968
M.S., Ph.D., University of Massachusetts: Amherst, MA, 1972, 1974

Publications

Burns, J. R. 1975. Seasonal changes in the reproduction of pumpkinseed, Lepomis gibbosus, correlated with temperature, day length, and stage of reproductive development. Physiological Zoology 48: 142-149.

Burns, J. R. 1976. The reproductive cycle and its environmental control in the pumpkinseed, Lepomis gibbosus (Pisces: Centrarchidae). Copeia  1976: 449-455.

Burns, J. R. 1979. The reproductive cycle and its environmental control in the pumpkinseed, Lepomis gibbosus (Pisces: Centrarchidae). In: Readings in Ichthyology, M. S. Love and G. M. Cailliet (Eds.),  pp. 388-393. Goodyear Publishing Company, Inc.,Santa Monica, California.

Burns, J. R. and J. A. Flores. 1981. Reproductive biology of the cuatro ojos, Anableps dowi (Pisces: Anablepidae), from El Salvador and its seasonal variations. Copeia 1981: 25-32.

Grier, H. J., J. R. Burns and J. A. Flores. 1981. Testis structure in three species of teleosts with tubular gonopodia, Anableps anableps, Anableps dowi and Jenynsia lineata. Copeia 1981: 797-801.

Wohlschlag, D. E., F. R. Parker, J. R. Burns and J. A. Kinney. 1981. Sensitivity of open Gulf fishes to ocean dumping wastes. Western Gulf of Mexico Dumping Site Assessment Report. Dumpsite Evaluation Report, pp. 297-315. NOAA Special Report. OAA/OMPA, Boulder, Colorado.

Burns, J. R. 1985. The effect of low-latitude photoperiods on the reproduction of female and male Poeciliopsis gracilis and Poecilia sphenops. Copeia 1985: 961-965.

Burns, J. R. and K. D. Kallman. 1985. An ovarian regression syndrome in the platyfish, Xiphophorus maculatus. Journal of Experimental Zoology 233: 301-316.

Knight, F. M., J. Lombardi, J. P. Wourms and J. R. Burns. 1985. Follicular placenta and embryonic growth of the viviparous four-eyed fish (Anableps). Journal of Morphology 185: 131-142.

Burns, J. R. 1987. Gonadotropic area development correlated with testis and gonopodial development in the cuatro ojos, Anableps dowi (Pisces: Anablepidae). In: Proc. Third Inter. Symp. Reprod. Physiol. Fish, D. R. Idler, L. W. Crim and J. M. Walsh (Eds.), p. 68. Marine Sciences Res. Lab., Memorial Univ. Newfoundland, St. John's, Newfoundland.

Burns, J. R. and M. A. Ramírez. 1990. Annual pattern of reproduction of the bagre, Arius guatemalensis (Pisces: Ariidae), in El Salvador. Revista de Biología Tropical 38(2B): 487-490.

Burns, J. R.  1991. Testis and gonopodium development in Anableps dowi (Pisces: Anablepidae) correlated with pituitary gonadotropic zone area. Journal of Morphology 210: 45-53.

Burns, J. R. and H. J. Grier. 1991. Testicular adaptations for internal fertilization in the glandulocaudine fishes (Teleostei: Characidae). In: Proc. Fourth Inter. Symp. Reprod. Physiol. Fish, A. P. Scott, J. P. Sumpter, D. E. Kime and M. S. Rolfe (Eds.), p. 97. FishSymp 91, Dept. Animal Plant Sciences, The University, Sheffield, U. K.

Flores, J. A. and J. R. Burns. 1993. Ultrastructural study of embryonic and early adult germ cells, and their support cells, in both sexes of Xiphophorus (Teleostei: Poeciliidae). Cell and Tissue Research 271: 263-270.

Bushmann, P. J. and J. R. Burns. 1994. Social control of sexual maturation in the swordtail characin, Corynopoma riisei (Gill). Journal of Fish Biology 44: 263-272.

Burns, J. R., S. H. Weitzman, H. J. Grier and N. A. Menezes. 1995. Internal fertilization, testis and sperm morphology in the glandulocaudine fishes (Teleostei: Characidae: Glandulocaudinae). Journal of Morphology 224: 131-145.

Downing, A. L. and J. R. Burns. 1995. Testis morphology and spermatozeugma formation in three genera of viviparous halfbeaks: Nomorhamphus, Dermogenys and Hemirhamphodon (Teleostei: Hemiramphidae). Journal of Morphology 225: 329-343.

Burns, J. R. and S. H. Weitzman. 1996. Novel gill-derived gland in the swordtail characin, Corynopoma riisei (Teleostei: Characidae: Glandulocaudinae). Copeia 1996: 627-633.

Meisner, A. D. and J. R. Burns. 1997. Testis and andropodial development in a viviparous halfbeak, Dermogenys sp. (Teleostei: Hemiramphidae). Copeia 1997: 44-52.

Burns, J. R., S. H. Weitzman and L. R. Malabarba. 1997. Insemination in eight species of cheirodontine fishes (Teleostei: Characidae: Cheirodontinae). Copeia 1997: 433-438.

Meisner, A. D. and J. R. Burns. 1997. Viviparity in the halfbeak genera Dermogenys and Nomorhamphus (Teleostei: Hemiramphidae). Journal of Morphology 234: 295-317.

Burns, J. R., S. H. Weitzman, K. R. Lange and L. R. Malabarba. 1998. Sperm ultrastructure in characid fishes, pp. 235-244. In: Phylogeny and Classification of Neotropical Fishes, L. R. Malabarba, R. E. Reis, R. P. Vari, Z. M. S. Lucena and C. A. S. Lucena (Eds.). Edipucrs, Porto Alegre, Brazil.

Malabarba, L. R., S. H. Weitzman and J. R. Burns. 1998. Compsurini Malabarba, Weitzman & Burns, new tribe, pp. 216-219, in Malabarba, L. R., Monophyly of the Cheirodontinae, characters and major clades (Ostariophysi: Characidae), pp. 193-233. In: Phylogeny and Classification of Neotropical Fishes, L. R. Malabarba, R. E. Reis, R. P. Vari, Z. M. S. Lucena and C. A. S. Lucena (Eds.). Edipucrs, Porto Alegre, Brazil.

Burns, J. R., S. H. Weitzman, L. R. Malabarba and A. D. Meisner. 2000. Sperm modifications in inseminating ostariophysan fishes, with new documentation of inseminating species, p. 255. In: Proc. Sixth Inter. Symp. Reprod. Physiol. Fish. B. Norberg, O.S. Kjesbu, G.L. Taranger, E. Andersson and S.O. Stefansson (Eds.). Inst. Mar. Res. and Univ. Bergen, Bergen, Norway.

Meisner, A. D., J. R. Burns and M. J. Ghedotti. 2000. Mode of embryonic nutrition in four species of Jenynsia (Teleostei: Atherinomorpha: Anablepidae), p. 178. In: Proc. Sixth Inter. Symp. Reprod. Physiol. Fish. B. Norberg, O.S. Kjesbu, G.L. Taranger, E. Andersson and S.O. Stefansson (Eds.). Inst. Mar. Res. and Univ. Bergen, Bergen, Norway.

Meisner, A. D., J. R. Burns, S. H. Weitzman and L R. Malabarba. 2000. Morphology and histology of the male reproductive system of two species of internally inseminating South American catfishes, Trachelyopterus lucenai and T. galeatus (Teleostei: Auchenipteridae). Journal of Morphology 246: 131-141.

Burns, J. R., A. D. Meisner, S. H. Weitzman and L. R. Malabarba. 2002. Sperm and spermatozeugma ultrastructure in the inseminating catfish, Trachelyopterus lucenai (Ostariophysi: Siluriformes: Auchenipteridae). Copeia 2002: 173-179.

Bushmann, P. J., J. R. Burns and S. H. Weitzman. 2002. Gill-derived glands in glandulocaudine fishes (Teleostei: Characidae: Glandulocaudinae). Journal of Morphology 253: 187-195.

Menezes, N. A., S. H. Weitzman and J. R. Burns. 2003. A systematic review of Planaltina (Teleostei: Characiformes: Characidae: Glandulocaudinae: Diapomini) with a description of two new species from the upper rio Paraná, Brazil. Proceedings of the Biological Society of Washington 116: 557-600.

Pecio, A., J. R. Burns and S. H. Weitzman. 2005. Sperm and spermatozeugma ultrastructure in the inseminating species Tyttocharax cochui, T. tambopatensis and Scopaeocharax rhinodus (Pisces: Teleostei: Characidae: Glandulocaudinae: Xenurobryconini). Journal of Morphology 263: 216-226.

Burns, J. R. and S. H. Weitzman. 2005. Insemination in ostariophysan fishes, pp. 107-135. In: Viviparous Fishes, M. C. Uribe and H. J. Grier (Eds.). New Life Publications, Homestead, Florida.

Weitzman, S. H., N. A. Menezes, H.-G. Evers and J. R. Burns. 2005. Putative relationships among inseminating and externally fertilizing characids, with a description of a new genus and species of Brazilian inseminating fish bearing an anal-fin gland in males (Characiformes: Characidae). Neotropical Ichthyology 3: 329-360.

Burns, J. R. and S. H. Weitzman. 2006. Intromittent organ in the genus Monotocheirodon (Characiformes: Characidae). Copeia 2006: 529-534.

Javonillo, R., J. R. Burns and S. H. Weitzman. 2007. Reproductive morphology of Brittanichthys axelrodi (Teleostei: Characidae), a miniature inseminating fish from South America. Journal of Morphology 268: 23-32.

Pecio, A., J. R. Burns and S. H. Weitzman. 2007. Comparison of spermiogenesis in the externally fertilizing Hemigrammus erythrozonus Durbin 1909 and the inseminating Corynopoma riisei, Gill 1858 (Teleostei: Characiformes: Characidae). Neotropical Ichthyology. 5: 457-470.

Oliveira, L. C. de, J. R. Burns, Luiz R. Malabarba and S. H. Weitzman. 2008. Sperm ultrastructure in the inseminating Macropsobrycon uruguayanae (Teleostei: Characidae: Cheirodontinae). Journal of Morphology 269: 691-697.

Burns, J. R., A. Pecio and S. H. Weitzman. 2008. Sperm and spermatozeugma structure in Xenurobrycon (Characiformes: Stevardiinae: Xenurobryconini). Copeia 2008: 656-660.

Burns, J. R., I. Quagio-Grassiotto and B. G. M. Jamieson. 2009. Ultrastructure of spermatozoa: Ostariophysi, pp. 287-387 (Chapter 11). In: Reproductive Biology and Phylogeny of Fish (Agnatha and Osteichthyes). Vol. A. Science Publishers, Enfield, NH, USA.

Javonillo, R., J. R. Burns and S. H. Weitzman. 2009. Sperm modifications related to insemination, with examples   from the Ostariophysi, pp. 721-761 (Chapter 17). In: Reproductive Biology and Phylogeny of Fish (Agnatha and Osteichthyes). Vol. A. Science Publishers, Enfield, NH, USA.

Javonillo, R., L. R. Malabarba, S. H. Weitzman and J. R. Burns. 2010. Relationships among major lineages of characid fishes (Teleostei: Ostariophysi: Characiformes), based on molecular sequence data. Molecular Phylogenetics and Evolution. 54:498-511.

Azevedo, M. A., L. R. Malabarba and J. R. Burns. 2010. Reproductive biology and development of gill glands in the inseminating characid, Macropsobrycon uruguayanae Eigenmann, 1915 (Cheirodontinae: Compsurini). Neotropical Ichthyology. 8:87-96.

Javonillo, R., J. R. Burns and S. H. Weitzman.  2010.  Sperm transfer: the first step toward viviparity, pp. 143-150.  In: Viviparous Fishes II, M. C. Uribe and H. J. Grier (Eds.).  NewLife Publications, Homestead, Florida.

Pecio, A., J. R. Burns and H. J. Grier.  2010.  Testis structure, spermiogenesis and spermatozoon ultrastructure in the four-eyed fish, Anableps anableps L. 1758 (Teleostei: Atherinomorpha: Cyprinodontiformes: Anablepidae), pp. 173-184. In: Viviparous Fishes II, M. C. Uribe and H. J. Grier (Eds.).  New Life Publications, Homestead, Florida.

de Oliveira, C. L. C., L. R. Malabarba, J. R. Burns and S. H. Weitzman. 2010. Sperm ultrastructure in three inseminating species of Compsurini (Teleostei: Characidae: Cheirodontinae), pp. 455-458. In: Viviparous Fishes II, M. C. Uribe and H. J. Grier(Eds.).  New Life Publications, Homestead, Florida.

Giora, J. and J. R. Burns. 2011. Sperm ultrastructure in three different families of weakly electric fishes (Teleostei: Gymnotiformes). Neotropical Ichthyology. 9:881-888.

Spadella, M. A., C. Oliveira, H. Ortega, I. Quagio-Grassiotto and J. R. Burns. 2012. Male and female reproductive morphology in the inseminating genus Astroblepus (Ostariophysi: Siluriformes:  stroblepidae). Zoologischer Anzeiger. 251:38-48.

de Oliveira, C. L. C., L. R. Malabarba and J. R. Burns. 2012. Comparative morphology of gill glands in externally fertilizing and inseminating species of cheirodontine fishes, with implications on the phylogeny of the family Characidae (Actinopterygii: Characiformes. Neotropical Ichthyology 10:349-360.

Quagio-Grassiotto, I., L. R. Malabarba, M. A. Azevedo, J. R. Burns, C. M. Baicere-Silva and R.Quevedo. 2012. Unique derived features in spermiogenesis and sperm morphology supporting a close relationship between the species of Rachoviscus and Hollandichthys (Teleostei: Characiformes). Copeia 2012:909-925.

Shrestha, B., R. Javonillo, J. R. Burns, Z. Pirger and A. Vertes. 2013. Comparative local analysis of metabolites, lipids and proteins in intact fish tissues by LAESI mass spectrometry. Analyst 138:3444-3449.

Classes Taught

BiSc 1112 - The Biology of Organisms
BiSc 2318 - Histology