David J. Innes Evolutionary genetics of reproduction

Bay Bulls, Newfoundland Spring 2000 (D. Innes)


Dr. David J. Innes
Department of Biology
Memorial University of Newfoundland
St. John's, Newfoundland, A1B 3X9, Canada
Phone: (709)737-4754 Fax: (709)737-3018
email: dinnes"at"mun.ca (replace at with @)

Research
The research in my laboratory focuses on sexual and asexual reproduction, primarily using the planktonic crustacean, Daphnia pulex as a model organism (visit the Cladoceran Web Site at the University of Guelph). We are also investigating the evolutionary genetics of the interaction between the mussels Mytilus edulis, M. trossulus and their hybrids in Newfoundland (in collaboration with Dr. Ray Thompson, Ocean Sciences Centre). Collaborative research is being carried out with Dr. Luise Hermanutz (Biology, MUN) on population and reproductive ecology of moss campion (Silene acaulis) and bog bean (Menyanthes trifoliata) in Newfoundland, and the reproductive ecology of Grevillea spp. in NSW Australia. Research on the population structure and mating systems in Newfoundland spiders has recently been initiated with Dr. Roger Pickavance.

A brief summary of current research:

Evolutionary interaction between sexual and asexual Daphnia pulex

Daphnia pulex occurs as two forms, cyclical parthenogens with sexual reproduction and obligate parthenogens with no sexual reproduction. Both forms co-occur in southern Ontario but are rarely found in the same pond. We have been determining sex allocation variation in the cyclical parthenogens and the avoidance of the cost of males in the obligate parthenogens. Some obligate parthenogen clones can produce males that can mate with sexual females from the cyclical parthenonogens and generate new obligately parthenogenetic clones. Current experiments are using microsatellite genetic markers to examine competition among males for mating with sexual females and determine the evolutionary dynamics of the formation of new obligately parthenogenetic clones.

Ecology and genetics of Mytilus spp. in Newfoundland

Two species of mussel (Mytilus edulis, M. trossulus) coexist along the coast of the island of Newfoundland. Limited hybridization occurs between the species which may be due to incompatibility between nuclear and cytoplasmic genes. In addition, we are investigating the role gamete choice may play in limiting hybridization.

For additional information see:

http://www.mun.ca/biology/dinnes/Mussels/Mussels.html

Genetic structure of moss campion (Silene acaulis)

Silene acaulis occurs as disjunct populations on the island of Newfoundland. Genetic differentiation appears to be high and the pattern is not related to geographic distance separating the populations. Genetic differences between populations on the east and west side of the island may be the result of different colonization patterns following post glaciation combined with random drift and limited gene flow.

Reproductive ecology of Australian Grevillea spp.

Members of the family Proteaceae have extremely low mature fruit : flower (FR : FL) ratios compared with other temperate, hermaphroditic, woody perennials. The role of compatibility in regulating FR : FL ratios was tested in five closely related species of Grevillea (Proteaceae). The correlation between self incompatibility and FR : FL ratios was non-significant, indicating that compatibility has a minimal effect on fruit set in the Grevillea species studied. Low FR : FL ratios may result from a combination of pollen limitation, and high levels of flower and fruit predation.

Reproductive ecology of Menyanthes trifoliata in Newfoundland
Menyanthes trifoliata is a distylous, clonal aquatic macrophyte found in shallowbogs and river margins throughout the boreal ecosystem, including the island of Newfoundland. A combination of long-distance dispersal and colonization after deglaciation, and pollen limitation resulting from reduced pollinator diversity and abundance documented on islands, predicts the breakdown of heterostyly to favour the establishment of self-compatible homostyles on islands. A strictly reciprocal arrangement of stigma height and anther length was not observed between pin and thrum morphs in the majority of populations studied. A reduced pollinator fauna typical of island environments may have relaxed stabilizing selection for strict herkogamy between floral morphs, resulting in the observed lack of reciprocity.

Genetic structure and mating behaviour in some Newfoundland spiders Three species of native ground running spiders were compared with an introduced orb weaving species for genetic differentiation over short and long geogrpahic distances. All species showed little evidence for genetic differentiation. It is unlikely that gene flow is high in these species and it is possible that large population size reduces the effect of genetic drift on population differentiation. Studies are also examining the mating behaviour in the orb weaver Araneus diadematus to determine if multiple mating occurs. Preliminary data suggest that if multiple mating occurs it is at a low level.

Photo Credits: Daphnia pulex (D. Innes); Mussel shell (D. Innes); Moss Campion(L. Hermanutz); Grevillea (Plant Systematics); Menyanthes (T. Schoepke); Spider (Spider Web Page)

Teaching
Biology 2250 Principles of Genetics

Biology 3295 Population and Evolutionary Ecology

Biology 2900 Principles of Evolution and Systematics

Biology 4250 Evolutionary Genetics

Biology 7290 Evolutionary Ecology

Students

Graduate Students

Wang Jue (Ph.D. in progress) Genetic structure of a mussel hybrid zone

Guangxu Liu (Ph.D. in progress) Genetic barriers to introgression in a mussel hybrid zone

Ben Lowen (Ph. D. in progress) Life history variation in a mussel hybrid zone

Marcelo Miranda (Ph.D. 2005) Genetics of hybridization in a mussel hybrid zone

James Fitzsimmons (M. Sc. 2006) Sex and evolution in Daphnia pulex

Jorge Toro (Ph.D. 1999) Natural hybridization in mussels

Barbara Saunders (M. Sc. 1998) Inheritance and linkage of RAPD markers in Daphnia

Undergraduate Thesis Students

Erin Stapleton 2006 Interactions between Mytilus edulis and M. trossulus spat

Michael Ginn 2005 Competition between cyclically and obligately parthenogenetic Daphnia pulex

Dax Rumsey 2002 Male production in the obligately parthenogeneic Cladoceran Daphnia pulex

Trina Kirby 2002 Mating system in the spider Araneus diadematus

Kerri Anstey 1999 Genetic variability and gene flow in five species of spiders found in Newfoundland (Pardosa hyperborea, Pardos moesta, Pardosa groenlandica, Cyclosa conica, & Araneus diadematus) determined using allozyme electrophoresis

Chris Fox 1998 Differences in ephippial production between obligate and cyclical parthenogenetic clones of Daphnia pulex

Geoff Winsor 1997 Sexual reproduction in Daphnia pulex: Observations on mating behaviour and avoidance of intra-clonal mating

Barbara Saunders 1995 RAPD genetic variation among populations of Daphnia pulex

Publications (complete list)

Papers: (1991 - 2006)

On Daphnia:

Fitzsimmons, J. M. & Innes, D. J. (2006) Inter-genotype variation in reproductive response to crowding among Daphnia pulex. Hydrobiologia 568:187-205 (download PDF file)

Tagg, N., Doncaster, C.P. & Innes, D. J. (2005) Outcomes of reciprocal invasions between genetically diverse and genetically uniform populations of Daphnia obtusa (Kurz). Oecologia 143: 527-536(download PDF file)

Fitzsimmons, J. M. & Innes, D. J. (2005) No evidence of Wolbachia among Great Lakes area populations of Daphnia pulex (Crustacea: Cladocera). Journal of Plankton Research 27:121-124 (download PDF file)

Tagg, N., Doncaster, C. P. & Innes, D. J. (2005) Resource competition between genetically varied and genetically uniform populations of Daphnia pulex (Leydig): does sexual reproduction confer a short-term ecological advantage? Biol. J. Linn. Soc. 85: 111-123 (download PDF file)

Winsor, G. L. & Innes, D. J. (2002) Sexual reproduction in Daphnia pulex (Crustacea: Cladocera): Observations on male mating behaviour and avoidance of inbreeding. Freshwater Biology 47: 441-450(download PDF file)

Innes, D. J. & Singleton, D. R. (2000) Variation in allocation to sexual and asexual reproduction among clones of cyclically parthenogenetic Daphnia pulex (Crustacea: Cladocera). Biol. J. Linn. Soc. 71(4): 771-787 (download PDF file)

Innes, D. J. , Fox, C. J. & Winsor, G. L. (2000) Avoiding the cost of males in obligately asexual Daphnia pulex (Leydig). Proc. Roy. Soc. B 267: 991-997 (download PDF file)

Innes, D. J. 1997 Sexual reproduction of Daphnia pulex in a temporary habitat. Oecologia 111, 53-60. (download PDF file)

Innes, D. J. & Singleton, D. R. 1994 Variation in reproduction and sex allocation among clones of Daphnia pulex, In Genetics and Evolution of Aquatic Organisms (ed. A. R. Beaumont), pp. 335-342. London: Chapman and Hall.

Innes, D. J. & Dunbrack, R. L. 1993 Sex allocation variation in Daphnia pulex. J. evol. Biol. 6, 559-575.

Innes 1991 Geographic patterns of genetic differentiation among sexual populations of Daphnia pulex. Can. J. Zool. 69, 995-1003.

On Mussels:

Toro, J. E., D. J. INNES and R. J. Thompson (2004) Genetic variation among life-history stages of mussels in a Mytilus edulis –M. trossulus hybrid zone. Marine Biology 145, 713-725. (download PDF file)

Toro, J. E., R. J. Thompson and D. J. INNES (2002) Reproductive isolation between coexisting mussel species (Mytilus edulis, M. trossulus) in Newfoundland. Marine Biology 141, 897–909. (download PDF file)

Comesana, A. S., Toro, J. E., Innes, D. J. & Thompson, R. J. 1999 A molecular approach to the ecology of a mussel (Mytilus edulis - M. trossulus) hybrid zone on the east coast of Newfoundland, Canada. Marine Biology 133, 213-221. (download PDF file)

Innes, D. J. & Bates, J. A. 1999 Morphological variation of Mytilus edulis and Mytilus trossulus in eastern Newfoundland. Marine Biology 133, 691-699. (download PDF file)

Jones, R., Bates, J. A., Innes, D. J. & Thompson, R. J. 1996 A quantitative genetic analysis of growth in larval scallops (Placopecten magellanicus). Marine Biology 124, 417-424.

Bates, J. A. & Innes, D. J. 1995 Genetic variation among populations of Mytilus spp. in eastern Newfoundland. Marine Biology 124, 417-424.

On plant mating systems and population genetics:

Thompson, F. L., Hermanutz, L. A. & Innes, D. J. 1999 The reproductive ecology of island populations of distylous Menyanthes trifoliata (menyanthaceae). Can. J. Bot 76, 818-828. (download PDF file)

Hermanutz, L. A., Innes, D. J., Denham, A. & Whelan, R. 1998 Very low fruit: flower ratios in Grevillea (Proteaceae) are independent of breeding system. Australian J. of Botany 46, 465-478. (download PDF file)

Rajora, O. P., Deverno, L., Mosseler, A. & Innes, D. J. 1998 Genetic diversity and population structure of disjunct Newfoundland and central Ontario populations of eastern white pine (Pinus strobus). Can. J. Bot. 76, 500-508. (download PDF file)

Hermanutz, L. A. & Innes, D. J. 1994 Gender variation in Silene acaulis (Caryophyllaceae). Plant Sytematics and Evolution 191, 69-81.

Go to Home Page

	Evolutionary interaction between sexual and asexual Daphnia pulex Daphnia pulex occurs as two forms, cyclical parthenogens with sexual reproduction and obligate parthenogens with no sexual reproduction. Both forms co-occur in southern Ontario but are rarely found in the same pond. We have been determining sex allocation variation in the cyclical parthenogens and the avoidance of the cost of males in the obligate parthenogens. Some obligate parthenogen clones can produce males that can mate with sexual females from the cyclical parthenonogens and generate new obligately parthenogenetic clones. Current experiments are using microsatellite genetic markers to examine competition among males for mating with sexual females and determine the evolutionary dynamics of the formation of new obligately parthenogenetic clones.
	Ecology and genetics of Mytilus spp. in Newfoundland Two species of mussel (Mytilus edulis, M. trossulus) coexist along the coast of the island of Newfoundland. Limited hybridization occurs between the species which may be due to incompatibility between nuclear and cytoplasmic genes. In addition, we are investigating the role gamete choice may play in limiting hybridization. For additional information see: http://www.mun.ca/biology/dinnes/Mussels/Mussels.html
	Genetic structure of moss campion (Silene acaulis) Silene acaulis occurs as disjunct populations on the island of Newfoundland. Genetic differentiation appears to be high and the pattern is not related to geographic distance separating the populations. Genetic differences between populations on the east and west side of the island may be the result of different colonization patterns following post glaciation combined with random drift and limited gene flow.
	*Reproductive ecology of Australian Grevillea* spp.** Members of the family Proteaceae have extremely low mature fruit : flower (FR : FL) ratios compared with other temperate, hermaphroditic, woody perennials. The role of compatibility in regulating FR : FL ratios was tested in five closely related species of Grevillea (Proteaceae). The correlation between self incompatibility and FR : FL ratios was non-significant, indicating that compatibility has a minimal effect on fruit set in the Grevillea species studied. Low FR : FL ratios may result from a combination of pollen limitation, and high levels of flower and fruit predation.
	*Reproductive ecology of Menyanthes trifoliata* in Newfoundland** Menyanthes trifoliata is a distylous, clonal aquatic macrophyte found in shallowbogs and river margins throughout the boreal ecosystem, including the island of Newfoundland. A combination of long-distance dispersal and colonization after deglaciation, and pollen limitation resulting from reduced pollinator diversity and abundance documented on islands, predicts the breakdown of heterostyly to favour the establishment of self-compatible homostyles on islands. A strictly reciprocal arrangement of stigma height and anther length was not observed between pin and thrum morphs in the majority of populations studied. A reduced pollinator fauna typical of island environments may have relaxed stabilizing selection for strict herkogamy between floral morphs, resulting in the observed lack of reciprocity.
	Genetic structure and mating behaviour in some Newfoundland spiders Three species of native ground running spiders were compared with an introduced orb weaving species for genetic differentiation over short and long geogrpahic distances. All species showed little evidence for genetic differentiation. It is unlikely that gene flow is high in these species and it is possible that large population size reduces the effect of genetic drift on population differentiation. Studies are also examining the mating behaviour in the orb weaver Araneus diadematus to determine if multiple mating occurs. Preliminary data suggest that if multiple mating occurs it is at a low level.
	Photo Credits: Daphnia pulex (D. Innes); Mussel shell (D. Innes); Moss Campion(L. Hermanutz); Grevillea (Plant Systematics); Menyanthes (T. Schoepke); Spider (Spider Web Page)