My lab strives to understand the integrative mechanisms (from molecule to organism) for how vertebrate animals tolerate and perform in challenging physical environments. We are interested in the physiological, cellular, and genomic bases of adaptation and acclimatization, particularly in response to hypoxia and/or temperature change. Physiological systems important for respiration and exercise are emphasized.
Ecology and Evolution; Environmental Physiology
Publications in Peer-Reviewed Journals
80) Scott, A.L., N.A. Pranckevicius, C.A. Nurse, and G.R. Scott. 2019. The regulation of catecholamine release from the adrenal medulla is altered in deer mice (Peromyscus maniculatus) native to high altitudes. Am. J. Physiol. Reg. Integr. Comp. Physiol. In press.
79) Du, S.N.N., J.A. Choi, E.S. McCallum, A.R. McLean, B.G. Borowiec, S. Balshine, and G.R. Scott. 2019. Metabolic implications of exposure to wastewater effluent in bluegill sunfish. Comp. Biochem. Physiol. C. Toxicol. Pharmacol. In press.
78) Ding, Y., S.A. Lyons, G.R. Scott, and T.E. Gillis. 2019. Characterizing the influence of chronic hypobaric hypoxia on diaphragmatic myofilament function and phosphorylation in high-altitude deer mice and low-altitude white-footed mice. J. Comp. Physiol. B. In press.
77) Storz, J.F. and G.R. Scott. 2019. Life ascending: mechanism and process in physiological adaptation to high-altitude hypoxia. In press.
76) McCallum, E.S., K.E. Nikel, H. Mehdi, S.N.N. Du, J.E. Bowman, J.D. Midwood, K.A. Kidd, G.R. Scott, and S. Balshine. 2019. Municipal wastewater effluent affects fish communities: a multi-year study involving two wastewater treatment plants. Environ. Pollut. 252, 1730-1741.
75) Storz, J.F., Z.A. Cheviron, G.B. McClelland, and G.R. Scott. 2019. Evolution of physiological performance capacities and environmental adaptation: insights from high-elevation deer mice (Peromyscus maniculatus). J. Mammal. 100, 910-922.
74) Ivy, C.M., S.L. Lague, J.M. York, B.A. Chua, L. Alza, R. Cheek, N.J. Dawson, P.B. Frappell, K.G. McCracken, W.K. Milsom, and G.R. Scott. 2019. Control of breathing and respiratory gas exchange in ducks native to high altitude in the Andes. J. Exp. Biol. 222, jeb198622.
73) McClelland, G.B. and G.R. Scott. 2019. Evolved mechanisms of aerobic performance and hypoxia resistance in high-altitude natives. Annu. Rev. Physiol. 81, 561-583.
72) Bose, A.P.H., B.G. Borowiec, G.R. Scott, and S. Balshine. 2019. Nesting on high: reproductive and physiological consequences of breeding across an intertidal gradient. Evol. Ecol. 33, 21-36.
71) Velotta, J.P., C.M. Ivy, C.J. Wolf, G.R. Scott, and Z.A. Cheviron. 2018. Maladaptive phenotypic plasticity in cardiac muscle growth is suppressed in high-altitude deer mice. Evolution. 72, 2712-2727.
70) Borowiec, B.G., G.B. McClelland, B.B. Rees, and G.R. Scott. 2018. Distinct metabolic adjustments arise from acclimation to constant hypoxia and intermittent hypoxia in killifish (Fundulus heteroclitus). J. Exp. Biol. 221, jeb190900.
69) Ivy, C.M. and G.R. Scott. 2018. Evolved changes in breathing and CO2 sensitivity in deer mice native to high altitudes. Am. J. Physiol. Reg. Integr. Comp. Physiol. 315, R1027-R1037.
68) Scott, G.R., K.H. Guo, and N.J. Dawson. 2018. The mitochondrial basis for adaptive variation in aerobic performance in high-altitude deer mice. Integr. Comp. Biol. 58, 506-518.
67) Hood, W.R., S.N. Austad, P. Bize, A.G. Jimenez, K.L. Montooth, P.M. Schulte, G.R. Scott, I. Sokolova, J.R. Treberg, and K. Salin. 2018. The mitochondrial contribution to animal performance, adaptation, and life-history variation. Integr. Comp. Biol. 58, 480-485.
66) Nikel, K.E., N.K. Shanishchara, C.M. Ivy, N.J. Dawson, and G.R. Scott. 2018. Effects of hypoxia at different life stages on locomotory muscle phenotype in deer mice native to high altitude. Comp. Biochem. Physiol. B. Biochem. Mol. Biol. 224, 98-104.
65) Dawson, N.J., S.A. Lyons, D.A. Henry, and G.R. Scott. 2018. Effects of chronic hypoxia on diaphragm function in deer mice native to high altitude. Acta Physiol. 223, e13030.
64) Ivy, C.M., J.M. York, S.L. Lague, B.A. Chua, L. Alza, K.G. McCracken, W.K. Milsom, and G.R. Scott. 2018. Validation of a pulse oximetry system for high-altitude waterfowl by examining the hypoxia responses of the Andean goose (Chloephaga melanoptera). Physiol. Biochem. Zool. 91, 859-867.
63) Du, S.N.N., E.S. McCallum, M. Vaseghi-Shanjani, J.A. Choi, T.R. Warriner, S. Balshine, and G.R. Scott. 2018. Metabolic costs of exposure to wastewater effluent lead to adjustments in respiratory physiology in bluegill sunfish. Environ. Sci. Technol. 52, 801-811.
62) Borowiec, B.G., C.M. O’Connor, K. Goodick, G.R. Scott, and S. Balshine. 2018. The preference for social affiliation renders fish willing to accept lower O2 levels. Physiol. Biochem. Zool. 91, 716-724.
61) Ivy, C.M. and G.R. Scott. 2017. Control of breathing and ventilatory acclimatization to hypoxia in deer mice native to high altitudes. Acta Physiol. 221, 266-282.
60) Lague, S.L., B. Chua, L. Alza, G.R. Scott, P.B. Frappell, Y. Zhong, A.P. Farrell, K.G. McCracken, Y. Wang, and W.K. Milsom. 2017. Divergent respiratory and cardiovascular responses to hypoxia in bar-headed geese and Andean birds. J. Exp. Biol. 220, 4186-4194.
59) Tate, K.B., C.M. Ivy, J.P. Velotta, J.F. Storz, G.B. McClelland, Z.A. Cheviron, and G.R. Scott. 2017. Circulatory mechanisms underlying adaptive increases in thermogenic capacity in high-altitude deer mice. J. Exp. Biol. 220, 3616-3620.
58) Hawkes, L.A., N. Batbayar, P.J. Butler, B. Chua, P.B. Frappell, J.U. Meir, W.K. Milsom, T. Natsagdorj, N. Parr, G.R. Scott, J.Y. Takekawa, M. Wikelski, M.J. Witt, and C.M. Bishop. 2017. Do bar-headed geese train for high altitude flights? Integr. Comp. Biol. 57, 240-251.
57) Mahalingam, S., G.B. McClelland, and G.R. Scott. 2017. Evolved changes in the intracellular distribution and physiology of muscle mitochondria in high-altitude native deer mice. J. Physiol. 595, 4785-4801.
56) Du, S.N.N., F. Khajali, N.J. Dawson, and G.R. Scott. 2017. Hybridization increases mitochondrial production of reactive oxygen species in sunfish. Evolution. 71, 1643-1652.
55) Lau, D.S., A.D. Connaty, S. Mahalingam, N. Wall, Z.A. Cheviron, J.F. Storz, G.R. Scott, and G.B. McClelland. 2017. Acclimation to hypoxia increases carbohydrate use during exercise in high-altitude deer mice. Am. J. Physiol. Reg. Integr. Comp. Physiol. 312, R400-R411.
54) York, J.M., B.A. Chua, C.M. Ivy, L. Alza, R. Cheek, G.R. Scott, K.G. McCracken, P.B. Frappell, N.J. Dawson, S.L. Laguë, and W.K. Milsom. 2017. Respiratory mechanics of eleven avian species resident at high and low altitude. J. Exp. Biol. 220, 1079-1089.
53) McCallum, E.S., S.N.N. Du, M. Vaseghi-Shanjani, J.A. Choi, T.R. Warriner, T. Sultana, G.R. Scott, and S. Balshine. 2017. In situ exposure to wastewater effluent reduces survival but has little effect on the behaviour or physiology of an invasive Great Lake fish. Aquat. Toxicol. 184, 37-48.
52) Lisser, D.F.J., Z.P. Lister, P.Q.H. Pham-Ho, G.R. Scott, and M.P. Wilkie. 2017. Relationship between oxidative stress and brain swelling in goldfish (Carassius auratus) exposed to high environmental ammonia. Am. J. Physiol. Reg. Integr. Comp. Physiol. 312, R114-R124.
51) Scott, G.R., V. Matey, J.A. Mendoza, K.M. Gilmour, S.F. Perry, V.M.F. Almeida-Val, and A.L. Val. 2017. Air breathing and aquatic gas exchange during hypoxia in armoured catfish. J. Comp. Physiol. B. 187, 117-133.
50) Ivy, C.M. and G.R. Scott. 2017. Ventilatory acclimatization to hypoxia in mice: methodological considerations. Respir. Physiol. Neurobiol. 235, 95-103.
49) Dawson, N.J., C.M. Ivy, L. Alza, R. Cheek, J.M. York, B. Chua, W.K. Milsom, K.G. McCracken, and G.R. Scott. 2016. Mitochondrial physiology in the skeletal and cardiac muscles is altered in torrent ducks, Merganetta armata, from high altitudes in the Andes. J. Exp. Biol. 219, 3719-3728.
48) Brunt, E., A.J. Turko, G.R. Scott, and P.A. Wright. 2016. Amphibious fish jump better on land after acclimation to a terrestrial environment. J. Exp. Biol. 219, 3204-3207.
47) Borowiec, B.G., K.D. Crans, F. Khajali, N.A. Pranckevicius, A. Young, and G.R. Scott. 2016. Interspecific and environment-induced variation in hypoxia tolerance in sunfish. Comp. Biochem. Physiol. A. Mol. Integr. Physiol. 198, 59-71.
46) Du, S.N.N., S. Mahalingam, B.G. Borowiec, and G.R. Scott. 2016. Mitochondrial physiology and reactive oxygen species production are altered by hypoxia acclimation in killifish (Fundulus heteroclitus). J. Exp. Biol. 219, 1130-1138.
45) Crans, K.D., N.A. Pranckevicius, and G.R. Scott. 2015. Physiological tradeoffs may underlie the evolution of hypoxia tolerance and exercise performance in sunfish (Centrarchidae). J. Exp. Biol. 218, 3264-3275.
44) Regan, M.D., R.S. Dhillon, D.P.L. Toews, B. Speers-Roesch, M.A. Sackville, S. Pinto, J.S. Bystriansky, and G.R. Scott. 2015. Biochemical correlates of aggressive behaviour in the Siamese fighting fish (Betta splendens). J. Zool. 297, 99-107.
43) Scott, G.R., T.S. Elogio, M.A. Lui, J.F. Storz, and Z.A. Cheviron. 2015. Adaptive modifications of muscle phenotype in high-altitude deer mice are associated with evolved changes in gene regulation. Mol. Biol. Evol. 32, 1962-1976.
42) Ivy, C.M. and G.R. Scott. 2015. Control of breathing and the circulation in high-altitude mammals and birds. Comp. Biochem. Physiol. A. Mol. Integr. Physiol. 186, 66-74.
41) Lui, M.A., S. Mahalingam, P. Patel, A.D. Connaty, C.M. Ivy, Z.A. Cheviron, J.F. Storz, G.B. McClelland, and G.R. Scott. 2015. High-altitude ancestry and hypoxia acclimation have distinct effects on exercise capacity and muscle phenotype in deer mice. Am. J. Physiol. Reg. Integr. Comp. Physiol. 308, R779-R791.
40) Borowiec, B.G., K.L. Darcy, D.M. Gillette, and G.R. Scott. 2015. Distinct physiological strategies are used to cope with constant hypoxia and intermittent hypoxia in killifish (Fundulus heteroclitus). J. Exp. Biol. 218, 1198-1211.
39) Scott, G.R., L.A. Hawkes, P.B. Frappell, P.J. Butler, C.M. Bishop, and W.K. Milsom. 2015. How bar-headed geese fly over the Himalayas. Physiology. 30, 107-115.
38) Bishop, C.M., R.J. Spivey, L.A. Hawkes, N. Batbayar, B. Chua, P.B. Frappell, W.K. Milsom, T. Natsagdorj, S.H. Newman, G.R. Scott, J.Y. Takekawa, M. Wikelski, and P.J. Butler. 2015. The roller coaster flight strategy of bar-headed geese conserves energy during Himalayan migrations. Science. 347, 250-254.
37) Schnurr, M.E., Y. Yin, and G.R. Scott. 2014. Temperature during embryonic development has persistent effects on muscle energy metabolism in zebrafish. J. Exp. Biol. 217, 1370-1380.
36) Hawkes, L.A., P.J. Butler, P.B. Frappell, J.U. Meir, W.K. Milsom, G.R. Scott, and C.M. Bishop. 2014. Maximum running speed of captive bar-headed geese is unaffected by severe hypoxia. PLoS One. 9, e94015.
35) De Boeck, G., C.M. Wood, F.I. Iftikar, V. Matey, G.R. Scott, K.A. Sloman, M. de Nazaré Paula da Silva, V.M.F. Almeida-Val, and A.L. Val. 2013. Interactions between hypoxia tolerance and food deprivation in Amazonian oscars, Astronotus ocellatus. J. Exp. Biol. 216, 4590-4600.
34) Hawkes, L.A., S. Balachandran, N. Batbayar, P.J. Butler, B. Chua, D.C. Douglas, P.B. Frappell, Y. Hou, W.K. Milsom, S.H. Newman, D.J. Prosser, P. Sathiyaselvam, G.R. Scott, J.Y. Takekawa, T. Natsagdorj, M. Wikelski, M.J. Witt, B. Yan, and C.M. Bishop. 2013. The paradox of extreme high altitude migration in bar-headed geese Anser indicus. Proc. R. Soc. B. 280, 20122114.
33) Scott, G.R. and I.A. Johnston. 2012. Temperature during embryonic development has persistent effects on thermal acclimation capacity in zebrafish. Proc. Natl. Acad. Sci. 109, 14247-14252.
32) Scott, G.R. 2011. Elevated performance: the unique physiology of birds that fly at high altitudes. J. Exp. Biol. 214, 2455-2462.
31) Scott, G.R., P.M. Schulte, S. Egginton, A.L.M. Scott, J.G. Richards, and W.K. Milsom. 2011. Molecular evolution of cytochrome c oxidase underlies high-altitude adaptation in the bar-headed goose. Mol. Biol. Evol. 28, 351-363.
30) Hawkes, L.A., G.R. Scott, J.U. Meir, P.B. Frappell, and W.K. Milsom. 2011. Last Word on Point:Counterpoint: High altitude is/is not for the birds! J. Appl. Physiol. 111, 1525.
29) Scott, G.R., J.U. Meir, L.A. Hawkes, P.B. Frappell, and W.K. Milsom. 2011. Point: High altitude is for the birds! J. Appl. Physiol. 111, 1514-1519.
28) Hawkes, L.A., S. Balachandran, N. Batbayar, P.J. Butler, P.B. Frappell, W.K. Milsom, N. Tseveenmyadag, S.H. Newman, G.R. Scott, P. Sathiyaselvam, J.T. Takekawa, M. Wikelski, and C.M. Bishop. 2011. The trans-Himalayan flights of bar-headed geese (Anser indicus). Proc. Natl. Acad. Sci. 108, 9516–9519.
27) Matey, V., F.I. Iftikar, G. De Boeck, G.R. Scott, K.A. Sloman, V.M.F. Almeida-Val, A.L. Val, and C.M. Wood. 2011. Gill morphology and acute hypoxia: responses of mitochondria-rich, pavement, and mucous cells in two species with very different approaches to the osmo-respiratory compromise, the Amazonian oscar (Astronotus ocellatus) and the rainbow trout (Oncorhynchus mykiss). Can. J. Zool. 89, 307-324.
26) Storz, J.F., G.R. Scott, and Z.A. Cheviron. 2010. Phenotypic plasticity and genetic adaptation to high-altitude hypoxia in vertebrates. J. Exp. Biol. 213, 4125-4136.
25) Scott, G.R., J.G. Richards, and W.K. Milsom. 2009. Control of respiration in flight muscle from the high-altitude bar-headed goose and low-altitude birds. Am. J. Physiol. Reg. Integr. Comp. Physiol. 297, R1066-R1074.
24) Scott, G.R., S. Egginton, J.G. Richards, and W.K. Milsom. 2009. Evolution of muscle phenotype for extreme high altitude flight in the bar-headed goose. Proc. R. Soc. B. 276, 3645-3653.
23) Takekawa, J.Y., S.R. Heath, D.C. Douglas, W.M. Perry, S. Javed, S.H. Newman, R.N. Suwal, A.R. Rahmani, B.C. Choudhury, D.J. Prosser, B. Yan, Y. Hou, N. Batbayar, T. Natsagdorj, C.M. Bishop, P.J. Butler, P.B. Frappell, W.K. Milsom, G.R. Scott, L.A. Hawkes, and M. Wikelski. 2009. Geographic variation in bar-headed geese Anser indicus: connectivity of wintering areas and breeding grounds across a broad front. Wildfowl. 59, 100–123.
22) Sloman, K.A., R.D. Sloman, G. De Boeck, G.R. Scott, F.I. Iftikar, C.M. Wood, V.M.F. Almeida-Val, and A.L. Val. 2009. The role of size in synchronous air-breathing of Hoplosternum littorale. Physiol. Biochem. Zool. 82, 625-634.
21) Wood, C.M., F.I. Iftikar, G.R. Scott, G. De Boeck, K.A. Sloman, V. Matey, F.X. Valdez Domingos, R. Duarte, V.M.F. Almeida-Val, and A.L. Val. 2009. Regulation of gill transcellular permeability and renal function during acute hypoxia in the Amazonian oscar (Astronotus ocellatus): new angles to the osmo-respiratory compromise. J. Exp. Biol. 212, 1949-1964.
20) Lee, S.Y., G.R. Scott, and W.K. Milsom. 2008. Have wing morphology or flight kinematics evolved for extreme high altitude migration in the bar-headed goose? Comp. Biochem. Physiol. C. Toxicol. Pharmacol. 148, 324-331.
19) Scott, G.R., C.M. Wood, K.A. Sloman, F.I. Iftikar, G. De Boeck, V.M.F. Almeida-Val, and A.L. Val. 2008. Respiratory responses to progressive hypoxia in the Amazonian oscar, Astronotus ocellatus. Respir. Physiol. Neurobiol. 162, 109-116.
18) Scott, G.R., D.W. Baker, P.M. Schulte, and C.M. Wood. 2008. Physiological and molecular mechanisms of osmoregulatory plasticity in killifish after seawater transfer. J. Exp. Biol. 211, 2450-2459.
17) Singer, T.D., K.R. Keir, M. Hinton, G.R. Scott, R.S. McKinley, and P.M. Schulte. 2008. Structure and regulation of the cystic fibrosis transmembrane conductance regulator (CFTR) gene in killifish: a comparative genomics approach. Comp. Biochem. Physiol. D. Genomics Proteomics 3, 172-185.
16) Scott, G.R., V. Cadena, G.J. Tattersall, and W.K. Milsom. 2008. Body temperature depression and peripheral heat loss accompany the metabolic and ventilatory responses to hypoxia in low and high altitude birds. J. Exp. Biol. 211, 1326-1335.
15) Scott, G.R. and W.K. Milsom. 2007. Control of breathing and adaptation to high altitude in the bar-headed goose. Am. J. Physiol. Reg. Integr. Comp. Physiol. 293, R379-R391.
14) Wood, C.M., M. Kajimura, K.A. Sloman, G.R. Scott, P.J. Walsh, V.M.F Almeida-Val, and A.L. Val. 2007. Rapid regulation of Na+ fluxes and ammonia excretion in response to acute environmental hypoxia in the Amazonian oscar, Astronotus ocellatus. Am. J. Physiol. Reg. Integr. Comp. Physiol. 292, R2048-R2058.
13) Dodd, G.A.A., G.R. Scott, and W.K. Milsom. 2007. Ventilatory roll off during sustained hypercapnia is gender specific in pekin ducks. Respir. Physiol. Neurobiol. 156, 47-60.
12) Scott, G.R. and W.K. Milsom. 2006. Flying high: a theoretical analysis of the factors limiting exercise performance in birds at altitude. Respir. Physiol. Neurobiol. 154, 284-301.
11) Scott, G.R., P.M. Schulte, and C.M. Wood. 2006. Plasticity of osmoregulatory function in the killifish intestine: drinking rates, salt and water transport, and gene expression after freshwater transfer. J. Exp. Biol. 209, 4040-4050.
10) Sloman, K.A., C.M. Wood, G.R. Scott, S. Wood, M. Kajimura, O.E. Johannsson, V.M.F. Almeida-Val, and A.L. Val. 2006. Tribute to R.G. Boutilier: The effect of size on the physiological and behavioural responses of oscar, Astronotus ocellatus, to hypoxia. J. Exp. Biol. 209, 1197-1205.
9) Scott, G.R., K.R. Keir, and P.M. Schulte. 2005. Effects of spironolactone and RU486 on gene expression and cell proliferation after freshwater transfer in the euryhaline killifish. J. Comp. Physiol. B. 175, 499-510.
8) Scott, G.R. and P.M. Schulte. 2005. Intraspecific variation in gene expression after seawater transfer in gills of the euryhaline killifish Fundulus heteroclitus. Comp. Biochem. Physiol. A. Mol. Integr. Physiol. 141, 176-182.
7) Scott, G.R., J.B. Claiborne, S.L. Edwards, P.M. Schulte, and C.M. Wood. 2005. Gene expression after freshwater transfer in gills and opercular epithelia of killifish: insight into divergent mechanisms of ion transport. J. Exp. Biol. 208, 2719-2729.
6) Scott, G.R., J.T. Rogers, J.G. Richards, C.M. Wood, and P.M. Schulte. 2004. Intraspecific divergence of ionoregulatory physiology in the euryhaline teleost Fundulus heteroclitus: possible mechanisms of freshwater adaptation. J. Exp. Biol. 207, 3399-3410.
5) Scott, G.R., J.G. Richards, B. Forbush, P. Isenring, and P.M. Schulte. 2004. Changes in gene expression in gills of the euryhaline killifish Fundulus heteroclitus after abrupt salinity transfer. Am. J. Physiol. Cell Physiol. 287, C300-C309.
4) Sloman, K.A., G.R. Scott, D.G. McDonald, and C.M. Wood. 2004. Diminished social status affects ionoregulation at the gills and kidney in rainbow trout (Oncorhynchus mykiss). Can. J. Fish. Aquat. Sci. 61, 618-626.
3) Scott, G.R. and K.A. Sloman. 2004. The effects of environmental pollutants on complex fish behaviour: integrating behavioural and physiological indicators of toxicity. Aquat. Toxicol. 68, 369-392.
2) Sloman, K.A., G.R. Scott, Z. Diao, C. Rouleau, C.M. Wood, and D.G. McDonald. 2003. Cadmium affects the social behaviour of rainbow trout, Oncorhynchus mykiss. Aquat. Toxicol. 65, 171-185.
1) Scott, G.R., K.A. Sloman, C. Rouleau, and C.M. Wood. 2003. Cadmium disrupts behavioural and physiological responses to alarm substance in juvenile rainbow trout (Oncorhynchus mykiss). J. Exp. Biol. 206, 1779-1790.
Book Chapters
4) Scott, G.R. and N.J. Dawson. 2016. Flying high: the unique physiology of birds that fly at high altitudes. Book chapter in The Biology of the Avian Respiratory System: Evolution, Development, Structure and Function. (ed. J.N. Maina), pp. 113-128. Heidelberg, Germany: Springer.
3) Hawkes, L.A., N. Batbayar, C.M. Bishop, P.J. Butler, P.B. Frappell, J.U. Meir, W.K. Milsom, T. Natsagdorj, and G.R. Scott. 2017. Goose migration over the Himalayas: physiological adaptations. Book chapter in Bird Migration Across the Himalayas: Wetland Functioning Amidst Mountains and Glaciers. (eds. H.H.T. Prins and T. Namgail), pp. 241-253. Cambridge, UK: Cambridge University Press.
2) McClelland, G.B. and G.R. Scott. 2014. Muscle Plasticity. Book chapter in The Physiology of Fishes, 4th Edition. (eds. D.H. Evans, J.B. Claiborne, and S. Currie), pp. 1-31. Boca Raton: CRC Press.
1) Scott, G.R. and W.K. Milsom. 2009. Control of breathing in birds: implications for high altitude flight. In Cardio-Respiratory Control in Vertebrates: Comparative and Evolutionary Aspects (eds. M.L. Glass and S.C. Wood), pp. 429-448. Berlin: Springer-Verlag.
