I study plant hybridization and speciation, phylogeography, molecular systematics and the molecular genetics of flower head development.

Research Group

Postdocs - Dr Guoqing Liu; Postgrads - Mr Joe Milton, Mr Gerld Hochschartner; Technician - Mr David Forbes

Hybridization and evolution

Interspecific hybridization occurs frequently in the plant kingdom and can result in interspecific gene flow and the origin of new allopolyploid and homoploid hybrid species. We are currently investigating the evolutionary consequences of hybridization in Senecio.

Senecio

Recent hybridization in the British Isles between native groundsel, Senecio vulgaris , and the introduced Oxford ragwort, S. squalidus, has resulted in:

1. the origin of a stabilised introgressant, S. vulgaris var. hibernicus;
2. the independent origin of the allohexaploid, S. cambrensis , in N Wales and Edinburgh;
3. the origin of the tetraploid hybrid species, S. eboracensis , in York.

These new taxa have been used as models for examining: (i) the origin and establishment of hybrid species in the wild; changes to transcriptome and genome during hybrid speciation in Senecio (in collaboration with Professor Simon Hiscock, Bristol University.

• Abbott R.J, Lowe A.J (2004) Origins, establishment and evolution of new polyploid species: Seneciocambrensis and S. eboracensis in the British Isles. Biol. J. Linn. Soc. (Special issue, In press)
• Lowe AJ, Abbott RJ (2004) Reproductive isolation of a new hybrid species, Senecio eboracensis Ê
  Abbott & Lowe. Heredity (In press)
• Abbott R, James JK, Milne RI & Gillies ACM (2003) Plant introductions, hybridization and gene flow. Phil. Trans. Royal Soc. B 358: 1123-1132.
• Abbott RJ (2003) Sex, sunflowers, and speciation. Science 301: 1189-1190.

Ê

Rhododendron

Many Rhododendron species are interfertile yet retain their identity in conditions of sympatry or parapatry. We have found a hybrid zone between two parapatric Rhododendron species in Turkey to be composed entirely of fertile F1 individuals (Richard Milne). The absence of later generation segregants and introgressants indicate that species barriers are maintained by severe post-F1 hybrid breakdown. We are currently investigating whether this phenomenon commonly maintains species barriers in the genus.
Rhododendron ponticum has become highly invasive in the British Isles following its introduction for horticultural purposes in the 18 th century. Molecular and morphological evidence shows that gene introgression has occurred from related R. catawbiense (also introduced) and may have led to an expansion of the range of R. ponticum into colder parts of the British Isles.

• Milne RI, Terzioglu S, Abbott RJ (2003) A hybrid zone dominated by fertile F1s: Maintenance of species barriers in Rhododendron . Molecular Ecology 12: 2719-2729.
• Milne RI, Abbott RJ (2000) Origin and evolution of invasive naturalised material of Rhododendron ponticum L. in the British Isles. Molecular Ecology 9: 541-556.

Phylogeography

A phylogeographic study of cpDNA variation in the arctic-alpine Purple saxifrage (Saxifraga oppositifolia) has provided evidence on how this species colonised the Arctic during the Pliocene, the locations of glacial refugia during Quaternary glaciations, and likely post-glacial migration routes during the Holocene. Phylogeographic analysis of Mediterranean Senecio based on surveys of cpDNA, ITS, RAPD and allozyme variation has provided information on how hybridisation and incomplete lineage sorting influences the partitioning of genetic variation within the group and has led to a better understanding of the group's evolutionary history.

• Abbott RJ, Comes HP (2004) Evolution in the Arctic: A phylogeographic analysis of the circumarctic plant Saxifraga oppositifolia (Purple saxifrage). New Phytologist (Special issue) 161: 211-224.
• Abbott RJ, Brochmann C (2003). History and evolution of the arctic flora: in the footsteps of Eric HultŽn. Molecular Ecology 12: 299-313.
• Abbott RJ, Smith LC, Milne RI, Crawford RMM, Wolff K, Balfour J (2000) Molecular analysis of plant migration and evolution in the Arctic. Science 289: 1343-1346.
• Comes HP , Abbott RJ (2001) Molecular phylogeography, reticulation and lineage sorting in the Mediterranean species complex of Senecio sect. Senecio (Asteraceae). Evolution 55: 1943-1962.

Molecular systematics

We are currently investigating the molecular systematics of the Myricaceae (Jane Herbert) and Senecio section Senecio (Joe Milton). Ê The Senecio work expands on a study of Mediterranean Senecio to include a phylogenetic analysis of representative taxa from South Africa and Australia.

Coleman M, Liston A, Kadereit JW, Abbott RJ (2003) Repeat intercontinental dispersal and Pleistocene speciation in disjunct Mediterranean and desert Senecio (Asteraceae). Am. J. Bot. 90: 1446-1454.
 

Molecular genetics of flower head development in the Asteraceae

The polymorphism for radiate versus non-radiate capitulum type in Senecio vulgaris is being used to investigate the molecular genetics of flower head development in the Asteraceae in collaboration with Rico Coen FRS (John Innes Institute).

Gillies ACM, Cubas P, Coen E.S, Abbott RJ (2002) Making rays in the Asteraceae: genetics and evolution of variation for radiate versus discoid flower heads. In Cronk QCB, Bateman RM, Hawkins JA (eds.) Developmental Genetics and Plant Evolution . Taylor & Francis, London. pp. 233-246.

Publications in international, citation indexed, peer reviewed journals:

Quinn, J. L., Cole, E. F., Bates, J., Payne, R., & Cresswell, W. (2011) Personality predicts individual responsiveness to risk of starvation and predation. Proceedings of the Royal Society: Series B in press.

Couchoux, C. & Cresswell, W. (2011) Personality constraints versus flexible anti-predation behaviours: how important is boldness in risk management of redshanks (Tringa totanus) foraging in a natural system. Behavioral ecology doi: 10.1093/beheco/arr185.

Quinn, J.L. & Cresswell, W. (2011) Local prey vulnerability increases with multiple attacks by a predator. Oikos in press.

Cox, D.T.C, Brandt, M.J., McGregor, R., Ottosson, U., Stevens, M.C. & Cresswell, W. (2011) Patterns of seasonal and yearly mass variation in West African tropical savannah birds. Ibis in press.

Cresswell, W. (2011) Predation in bird populations. Journal of Ornithology 152 (Suppl 1):S251-S263.

Lord, A.M, McCleery, R. & Cresswell, W. (2011) Incubation prior to clutch completion accelerates embryonic development and so hatch date for eggs laid earlier in a clutch in the Great tit, Parus major. Journal of Avian Biology 42: 187-191.

Cresswell, W. & Quinn, J.L. (2011) Predicting the optimal group-size from predator hunting behaviour. Journal of Animal Ecology 80: 310-319.

Wilson, J.M. & Cresswell , W. (2010) Densities of Palearctic warblers and Afrotropical species within the same guild in Sahelian West Africa. Ostrich 81:225-232.

Cresswell, W. & Quinn, J.L. (2010) Attack frequency, attack success and choice of prey group size for two predators with contrasting hunting strategies. Animal Behaviour 80: 643-648.

Manu, S., Imong, I.S. & Cresswell W. (2010) Bird species richness and diversity at montane IBA sites in South Eastern Nigeria. Bird Conservation International 20:231-239.

Wilson, J.M. & Cresswell , W. (2010) The Northern Wheatear Oenanthe oenanthe in the Sahel of West Africa: distribution, seasonal variation in abundance and habitat associations. Ostrich 81:115-121.

Stevens, M.C., Sheehan, D.K., Wilson, J.M., Buchanan, G.M. & Cresswell, W. (2010) Changes in Sahelian bird biodiversity and tree density over a five year period in Northern Nigeria. Bird Study 57:156-174.

Cresswell, W., Lind, J. & Quinn, J.L. (2010) Predator hunting success and prey vulnerability: quantifying the spatial scale over which lethal and non-lethal effects of predation occur. Journal of Animal Ecology 79:556-562.

Jones, T. & Cresswell, W. (2010) The phenology mismatch hypothesis: Are declines of migrant birds linked to uneven global change? Journal of Animal Ecology 79:98-108.

Sansom, A., Lind, J. & Cresswell, W. (2009) Individual behaviour and survival: the roles of predator avoidance, foraging success and vigilance. Behavioral Ecology 20:1168-1174.

Cresswell, W., Clark, J. & Macleod, R. (2009) How climate change might influence the starvation-predation risk trade-off response. Proceedings of the Royal Society: Series B 276: 3553-3560.

W. Cresswell, W., Butler, S., Whittingham, M.J. &  Quinn. J.L. (2009) Very short delays prior to escape from potential predators may function efficiently as adaptive risk-assessment periods. Behaviour 146:795-813.

Brandt, M.J. & Cresswell W. (2009) Diurnal foraging routines in a tropical bird, the rock finch Lagonosticta sanguinodorsalis: how important is predation risk? Journal of Avian Biology 40:90-94.

Macleod, R., Clark, J. & Cresswell, W. (2008) The starvation-predation risk trade-off, body mass and population status in the Common Starling Sturnus vulgaris. Ibis 150 S1:199-208.

Cresswell W. & Whitfield D.P. (2008) How starvation risk in Redshanks results in predation mortality from Sparrowhawks. Ibis 150 S1:209-218.

Brandt, M.J. & Cresswell W. (2008) Breeding behaviour, home range and habitat selection in Rock Firefinches (Lagonosticta sanguinodorsalis) in the wet and dry season in central Nigeria. Ibis 150:495-507.

Sansom, S., Cresswell W., Minderman, J. & Lind, L. (2008) Vigilance benefits and competition costs in groups: do individual redshanks gain an overall foraging benefit? Animal Behaviour 75:1869-1875.

Cresswell, W. (2008) Non-lethal effects of predation risk in birds. Ibis150:3-17.

Garcia-del-Rey, E., Cresswell, W., Perrins, C.M. & Gosler, A.G. (2007). Evolutionary trends and extreme cases of life history traits in the Blue Tit (Parus caeruleus) on oceanic islands (Canary Islands). Ardeola 54:27-39.

Garcia-del-Rey, E., & Cresswell, W.  (2007). The breeding biology of the endemic Berthelot’s Pipit Anthus berthelotii in a harsh oceanic island environment (Tenerife, Canary Islands). Ostrich 78:583-589.
 
MacLeod, R., Lind,J., Clark J., & Cresswell W. (2007) Mass regulation in response to predation risk can indicate population declines. Ecology Letters 10: 945-955.

McGregor, R., Whittingham, M.J. & Cresswell, W. (2007) Survival rates of tropical birds in Nigeria, West Africa. Ibis 149:615-618.

Cresswell, W., Wilson, J.M., Vickery J., Jones, P. & Holt, S. (2007) Changes in densities of Sahelian bird species in response to recent habitat degradation. Ostrich 78:247-253.

Wilson, J.M. & Cresswell, W. (2007) Identification of potentially competing Afrotropical and Palearctic bird species in the Sahel. Ostrich 78:363-368.

McGregor, R.M., Ottosson, U. & Cresswell W. (2007) Moult of guinea savanna passerines in West Africa. Ostrich 78:287-290.

Manu, S. & Cresswell W. (2007) Addressing sampling bias in counting forest birds: a West African case study. Ostrich 78:281-286.

Cresswell, W., Lind, J., Quinn, J.L., Minderman, J. & Whitfield, D.P.  (2007) Ringing or colour-banding does not increase predation mortality in redshanks. Journal of Avian Biology 38:309-316.

Manu, S., Peach, W. & Cresswell, W. (2007) The effects of fragment size and degree of isolation on avian species richness in highly fragmented forest in West Africa. Ibis 149:287-297.

Watson, M., Aebischer, N.J. & Cresswell W. (2007) Vigilance and fitness in grey partridges Perdix perdix: the effects of group size and foraging-vigilance trade-offs on predation mortality. Journal of Animal Ecology 76:211-221.

Quinn, J.L., Whittingham, M.J., Butler, S.J. & Cresswell, W. (2006) Noise, predation risk compensation and vigilance in the chaffinch Fringilla coelebs. Journal of Avian Biology 37:601-608.

Wilson, J.M. & Cresswell, W. (2006) How robust are Palearctic migrants to habitat loss and degradation in the Sahel? Ibis 148:789-800.

Quinn, J.L. & Cresswell, W. (2006) Testing domains of danger in the selfish herd: sparrowhawks target widely spaced redshanks in flocks. Proceedings of the Royal Society: Series B 273:2521-2526.

Watson M., Wilson J. M., Koshkin M., Sherbakov B., Karpov F., Gavrilov A., Schielzeth, H., Brombacher M., Collar N.J. & Cresswell W. (2006) Nest survival and productivity of the critically endangered Sociable Lapwing Vanellus gregarious. Ibis 148:489-502.

Garcia-del-Rey, E., Cresswell, W., Perrins, C. & Gosler, A. (2006) Variable effects of laying date on clutch size in the Canary Island Blue Tits (group). Ibis 148:564-567.   

Minderman, J., Lind, J. & Cresswell W. (2006) Behaviourally mediated indirect effects: Interference competition increases predation mortality in foraging redshanks. Journal of Animal Ecology 75:713-723.

Lind, J. & Cresswell, W. (2006) Anti-predation behaviour during bird migration; the benefit of studying multiple behavioural dimensions. Journal of Ornithology 147:310-316.

MacLeod R., Barnett P., Clark J., Cresswell W. (2006) Mass-dependent predation risk as a mechanism for house sparrow declines? Biology Letters 2:43-46.

Butler,S.J., Whittingham,M.J., Quinn,J.L. & Cresswell,W. (2006) Time in captivity and individual differences influence experimental success: foraging trials on wild-caught chaffinches. Behaviour 143: 535-548.

Garcia-del-Rey, E. & Cresswell, W. (2006) Population size and habitat selection of the Feurteventura Blue Tit (Parus caeruleus degener). Ostrich 77:105-108.

Garcia-del-Rey, E. & Cresswell, W. (2005) Density estimates, microhabitat selection, and foraging behaviour of the endemic blue chaffinch Fringilla teydae teydae on Tenerife (Canary Islands). Ardeola 52: 305-317.

Manu, S., Peach, W., Bowden, C. & Cresswell W. (2005) The effects of forest fragmentation on the population density and distribution of the globally endangered Ibadan Malimbe Malimbus ibadanensis. Bird Conservation International 15: 275-285.

Quinn, J.L. & Cresswell, W. (2005) Personality and anti-predation behaviour in the chaffinch Fringilla coelebs. Behaviour 142: 1383-1408.

MacLeod, R., Gosler, A. & Cresswell, W. (2005). Diurnal mass gain strategies and perceived predation risk in the great tit, Parus major. Journal of Animal Ecology 74:956-964.

Lind, J. & Cresswell, W. (2005). Determining the fitness consequences of anti-predation behaviour. Behavioral Ecology 16:945-956.

Quinn, J.L. & Cresswell, W. (2005) Escape response delays in wintering redshank Tringa totanus flocks are explained by the perceptual limit and economic hypotheses. Animal Behaviour 69:1285-1292.

Githiru, M., Lens, L. & Cresswell W. (2005) Nest predation in a fragmented Afrotropical forest: evidence from natural and artificial nests. Biological Conservation 123:189-196.

MacLeod, R., Barnett, R.B., Clark, J. & Cresswell, W. (2005) Body mass change strategies in blackbirds Turdus merula: the starvation-predation risk trade-off. Journal of Animal Ecology 74:292-302.

Butler,S.J., Whittingham,M.J., Quinn,J.L. & Cresswell,W. (2005) Quantifying the interaction between food density and habitat structure in determining patch selection. Animal Behaviour 69:337-343.

Whittingham,M.J., Butler,S.J., Quinn,J.L. & Cresswell,W. (2004) The effect of limited visibility on vigilance behaviour and speed of predator detection. Oikos 106:377-385.

Cresswell, W., Holt, S., Reid, J.M., Whitfield, D.P., Mellanby, R.J., Norton, D., & Waldron, S. (2004) The energetic costs of egg heating constrain incubation attendance but do not determine daily energy expenditure in the Pectoral Sandpiper. Behavioral Ecology 15:498-507.

Catry, P., Campos, A., Almada, V. & Cresswell, W. (2004) Winter segregation of migrant European Robins Erithacus rubecula in relation to sex, age and size. Journal of Avian Biology 35:204-209.

Quinn, J.L. & Cresswell, W. (2004). Predator hunting behaviour and prey vulnerability. Journal of Animal Ecology 73:143-154.

Cresswell, W. & Quinn, J. (2004). Faced with a choice, predators select the most vulnerable group: implications for both predators and prey for monitoring relative vulnerability. Oikos 104:71-76.

Yasué, M., Quinn, J.L. & Cresswell, W. (2003). Multiple effects of weather on the starvation and predation risk trade-off in choice of feeding location in redshanks. Functional Ecology 17:727-736.

Cresswell, W., Lind, J., Kaby, U., Quinn, J.L. & Jakobsson, S. (2003). Does an opportunistic predator preferentially attack non-vigilant prey? Animal Behaviour 66: 643-648.

Cresswell,W. (2003). Testing the mass-dependent predation hypothesis: in European blackbirds poor foragers have higher overwinter body reserves. Animal Behaviour 65:1035-1044.

Cresswell, W., Quinn, J.L., Whittingham, M.J., & Butler, S. (2003). Good foragers can also be good at detecting predators. Proceedings of the Royal Society: Series B 270:1069-1076.

Cresswell W. & McCleery, R. (2003) How great tits maintain synchronisation of their hatch date with food supply in response to long term variability in temperature. Journal of Animal Ecology 72:356-366.

Cresswell, W., Holt, S., Reid, J.M., Whitfield, D.P. & Mellanby, R.J. (2003) Do the energetic demands of incubation constrain incubation scheduling in a biparental species. Behavioral Ecology 14:97-102.

Smith, R.D., Ruxton, G.D. & Cresswell, W. (2002) Do kleptoparasites reduce their own foraging effort in order to detect kleptoparasitic opportunities? An empirical test of a key assumption of kleptoparasitic models. Oikos 97: 205-212.

Reid, J.M., Cresswell, W., Holt, S., Mellanby, R.J., Whitfield, D.P. & Ruxton, G.D. (2002). Nest scrape design and clutch heat loss in Pectoral Sandpipers (Calidris melanotos). Functional Ecology 16:305-312.

McGowan, A., Cresswell, W. & Ruxton, G.D. (2002) The effects of daily weather variation on foraging and responsiveness to disturbance in overwintering Red Knot (Calidris canutus). Ardea 90:229-237.

Smith, R.D., Ruxton, G.D. & Cresswell, W. (2001) Patch choice decisions of wild blackbirds: the role of pre-harvest public information Animal Behaviour 61:1113-1124.

Smith, R.D., Ruxton, G.D. & Cresswell, W. (2001) Dominance and feeding interference in small groups of blackbirds Behavioral Ecology 12:475-481.

Cresswell, W. (2001). Relative competitive ability does not change over time in blackbirds. Journal of Animal Ecology 70:218-227.

Cresswell, W. , Smith, R.D. & Ruxton, G.D. (2001). Absolute foraging rate and susceptibility to interference competition in blackbirds varies with patch conditions. Journal of Animal Ecology 70:228-236.

Cresswell, W. Hilton, G.M.,& Ruxton, G.D. (2000) Evidence for a rule governing the avoidance of superfluous escape flights. Proceedings of the Royal Society: Series B 267:1069-1076.

Cresswell, W. (1999). Travel distance and mass gain in wintering blackbirds. Animal Behaviour 58:1109-1116.

Hilton, G.M., Ruxton, G.D. & Cresswell, W. (1999) Choice of foraging area with respect to predation risk in redshanks: the effects of weather and predator activity. Oikos 87:295-302.

Hilton, G.M., Cresswell, W. & Ruxton, G.D. (1999) Intra-flock variation in the speed of escape-flight response on attack by an avian predator. Behavioural Ecology 10: 391-395.

Whitfield D.P., Cresswell W., Ashmole N.P., Clark N.A. & Evans A.D. (1999) No evidence for Sparrowhawks selecting Redshanks according to size and condition. Journal of Avian Biology 30:31-39.

Cresswell, W., Yerokhov, S., Berezovikov, N., Mellanby, R., Bright, S., Catry, P., Chaves, J., Freile, J., Gretton, A., Zykin, A., McGregor, R. & McLaughlin, D. (1999). Important wetlands in northern and eastern Kazakstan. Wildfowl 50:181-194.

Vickery, J., Thomas D., Rowcliffe, M., Cresswell, W., Jones, P. & Holt, S. (1999) Habitat selection of whitethroats during spring passage in the Sahel zone of northern Nigeria. Bird Study 46: 348-355.

Cresswell, W., M. Hughes, R. Mellanby, S. Bright, P. Catry, J. Chaves, J. Freile, A. Gabela, H. Martineau, R. MacLeod, F. McPhee, N. Anderson, S. Holt, S. Barabas, C. Chapel & T. Sanchez (1999) Densities and habitat preferences of Andean cloud-forest birds in pristine and degraded habitats in northeastern Ecuador. Bird Conservation International 9:124-145.

Cresswell, W. (1998) Relative competitive ability changes with competitor density: evidence from foraging blackbirds. Animal Behaviour 56:1367-1373.

Cresswell, W. (1998) Variation in the strength of interference competition with resource density in blackbirds Turdus merula. Oikos 81:152-160.

Cresswell, W. (1998) Diurnal and seasonal mass variation in blackbirds Turdus merula: consequences for mass-dependent predation risk. Journal of Animal Ecology 67:78-90.

Cresswell, W. (1997) Interference competition at low competitor densities in blackbirds Turdus merula. Journal of Animal Ecology 66:461-471.

Cresswell, W. (1997) Nest predation rates and nest detectability at different stages of breeding in blackbirds Turdus merula. Journal of Avian Biology 28:296-302.

Cresswell, W. (1997) Nest predation: the relative effects of nest characteristics, clutch size and parental behaviour. Animal Behaviour 53:93-103.

Cresswell, W., Irwin, M., Jensen, M., Mee, A., Mellanby, R., McKean, M. & Milne, L. (1997) Population estimates and distribution changes of landbirds on Silhouette Island, Seychelles. Ostrich 68: 50-57.

Cresswell, W. (1996) Surprise as a winter hunting strategy in Sparrowhawks Accipiter nisus, Peregrines Falco peregrinus and Merlins F. columbarius. Ibis 138:684-692.

Jones, P., Vickery, J., Holt, S., & Cresswell, W. (1996) A preliminary assessment of some factors influencing the density and distribution of Palearctic passerine migrants wintering in the Sahel zone of West Africa. Bird Study 43:73-84.

Cresswell, W. (1995) Selection of avian prey by wintering sparrowhawks Accipiter nisus in southern Scotland. Ardea 83:381-389.

Cresswell, W. (1994) Age-dependent choice of redshank (Tringa totanus) feeding location: profitability or risk? Journal of Animal Ecology 63:589-600.

Cresswell, W. (1994) Flocking is an effective anti-predation strategy in Redshanks, Tringa totanus. Animal Behaviour 47: 433-442.

Cresswell, W. (1994) The function of alarm calls in redshanks, Tringa totanus. Animal Behaviour 47:736-738.

Cresswell, W. (1994) Song as a pursuit-deterrent signal, and its occurrence relative to other anti-predation behaviours of skylark (Alauda arvensis) on attack by merlins (Falco columbarius). Behavioural Ecology and Sociobiology 34:217-223.

Cresswell, W. & Whitfield, D.P. (1994) The effects of raptor predation on wintering wader populations at the Tyninghame estuary, southeast Scotland. Ibis 136:223-232.

Cresswell, W. (1993) Escape responses by redshanks, Tringa totanus, on attack by avian predators. Animal Behaviour 46:609-611.
 

Other peer reviewed publications:

Cresswell, W. (2010) Empirical studies of predator and prey behaviour. In Breed, M. D. & Moore, J., eds. Encyclopedia of Animal Behavior , pp 633-638. Oxford: Academic Press.

Cresswell, W., Boyd, M. & Stevens, M. (2009). Movements of Palearctic and Afrotropical bird species during the dry season (November–February) within Nigeria. pp. 18–28. In: Harebottle, D.M., Craig, A.J.F.K., Anderson, M.D., Rakotomanana, H. & Muchai. (eds). Proceedings of the 12th Pan African Ornithological Congress, 2008. Cape Town, Animal Demography Unit.

Cresswell, W. (2009) The use of mass and fat reserve measurements from ringing studies to assess body condition. Ringing & Migration 24: 227-232.

Manu, S., Peach, W. & Cresswell, W. (2005). Notes on the natural history of the Ibadan Malimbe Malimbus ibadanensis, a threatened Nigerian endemic. Malimbus 27:33-39.
Cresswell, W. (2004) Kleptoparasitism rates and aggressive interactions between raptors. In Raptors Worldwide: Proceedings of the 6th World Conference on Birds of Prey and Owls. Chancellor, R. D. & B.-U. Meyburg eds. pp 805 – 814.

Manu, S. & Cresswell, W. (2002). The effects of forest fragmentation on Palearctic migrants in south western Nigeria. In Wings Over Africa: Proceedings of the International Seminar on Bird Migration: Research, Conservation, Education and Flight Safety (Eds. Leshem, Y., Froneman, A., Mundy, P. Shamir, H.), pp 143 – 150. International Center for the Study of Bird Migration, Israel.

Cresswell, W., R. Mellanby, S. Bright, P. Catry, J. Chaves, J. Freile, A. Gabela, M. Hughes, H. Martineau, R. MacLeod, F. McPhee, , N. Anderson, S. Holt, S. Barabas, C. Chapel & T. Sanchez. (1999) Birds of the Guandera Reserve, Carchi province, northeastern Ecuador. Cotinga 11:55-63.

Cresswell, W. (1997). Carrion crows catching waders. British Birds 90:366.

Cresswell, W. (1997). Caching of prey by carrion crows. British Birds 90 366-367.

 

Maternally deposited testosterone in eggs and differential maternal investment in the zebra finch.

While differential female investment in the offspring of particular males has been described before, we found that female zebra finches deposit more testosterone in the yolks of their eggs when they have a more attractive mate (easily manipulated in this species). We have since found that the behaviour, growth and maturation rate of the offspring are affected by this increased concentration of testosterone. We are currently examining the effects on dominance, sexual dimorphism and of these effects and the dynamics of this differential investment. We have also found that female zebra finches skew the sex ratio of their eggs in response to diet quality, but not in response to the attractiveness of their mate.

Researchers : Pati Celis, Lucy Gilbert, Neil Hazon, Kathryn Williamson. Funded by the BBSRC.

• Gil D, Graves J, Hazon N, Wells A (1999) Male attractiveness and differential testosterone investment in zebra finch eggs. Science 286, 126-128.
• Gil D, Graves J (2001) Differential allocation and good genes. Trends Ecol & Evol 16: 21-22.
• Rutstein AN, Slater PJB, Graves JA (in press) Diet quality and resource allocation in the zebra finch. Biological Letters .
• Rutstein AN,Gilbert,L, Slater PJB, Graves JA (in press) Mate attractiveness and differential allocation in zebra finches. Animal Behavour
  
  

Measurements of Relatedness and Population Structure in Seals

Grey seals breed in spatially structured, colonial groups with high levels of synchrony in breeding and show high levels of philopatry potentially resulting in aggregations of related individuals. We are using microsatellites to look at relatedness between individual female grey seals and the effects on the interactions with their neighbours. Very recently we have used these and other molecular markers to examine the population structure of grey seals in the Baltic and have just begun to do the same with the populations of ringed seals breeding around Svalbard working with the Norwegian Polar Institute in Tromso.

Researchers : Olle Karlsson, Kit Kovacs, Veronica Poland, Paddy Pomeroy

Communal nesting and reproductive skew

Most avian communal breeding systems are characterised by only one breeding pair per group plus non-breeding helpers, but in some there are two or more breeding females in the group. This reproductive sharing has been explained as the result of reproductive incentives by controlling dominants to keep subordinates in the group or incomplete control over reproduction by dominants. Measurements of reproductive skew are fundamental to understanding the evolution and maintenance of these breeding systems and we are using microsatellite markers to measure this in two very different communal breeding systems. 1) In the ostrich multiple, unrelated females lay in a nest, but only one female contributes to incubation and brooding. 2) The guira cuckoo almost always breeds in groups of related and unrelated birds with up to 7 females laying in a joint, cooperatively built nest. All contribute to incubation, vigilance and nest defence , but they also show high levels of conflict. Adults eject eggs and even nestlings from the communal nest, sometimes leading to the loss of the entire brood.

Researchers : Charles Kimwele, Regina Macedo, Laura Muniz

Funded by NERC, National Geographic Society and el Conselho Nacional de Desenvolvimento de Ciencia e Tecnologia, and British Council.

• Kimwele CN, Graves J, Burke T, Hanotte T (1998) Development of microsatellite markers for parentage typing of chicks using hatched eggs in the ostrich, Struthio camelus . Molecular. Ecology 7: 247-255.
• Kimwele CN, Graves JA (2003) A molecular genetic analysis of the communal nesting of the ostrich ( Struthio camelus ). Molecular Ecology 12: 229-236.
• Muniz L, Macedo RF, Graves JA (2003) Isolation and characterization of dinucleotide microsatellite loci in communally breeding guira cuckoos (Aves: Cuculidae). Molecular Ecology Notes 3: 209-211.
  Macedo RHF, Cariello MO, Graves JA, Schwabl H (2003) Reproductive partitioning in communally breeding guira cuckoos, Guira guira. Behav. Ecol. Sociobiol. Published online Nov 2003.

Mechanisms and content of marinemammal vocal interactions

Two of the main questions we ask in our lab is how marine mammalscommunicate and what kind of information they exchange. This requiresthedetailed analysis of vocal interactions in captivity and in the wild.We usepassive acoustic localization to ascribe sounds to individuals. Thisallows usto correlate different types of vocalizations or interactions withbehaviouralcontexts. Using these methods we describe the use of vocalizationsduringforaging and social interactions in dolphins and seals. This alsoincludes theexperiemtnal investigation of vocal learning, one of the mechanismsthat can beused to introduce novel signals into a communication system.

Referential communication andindividual identity

Signature whistles are individually distinctive signals given bybottlenosedolphins in isolation contexts. Unlike isolation calls of other animalstheyare learned and can be copied by conspecifics. This kind of copying canbe usedto address a specific individual. Our studies investigate whetherdolphins arecapable to use voice cues and how background noise and water pressureaffectdolphin signals and consequently voice recognition. We also study theindividual recognition skills of dolphins to explore their naturalability touse learned labels, a crucial step in the evolution of referentialcommunication.This is done by using playback techniques in the wild anddiscriminationexperiments with captive individuals. Comparative work on other speciestriesto identify conditions that lead to the evolution of these skills.

Geographic variation and traditions in behaviour patterns

Marine mammals show a substantialamount of geographic variation in their behaviour patterns. Even withinthesame species vocal repertoires differ between different sites. This maybecaused directly by differences in habitat or indirectly through theeffects ofthe environment on the social behaviour and social structure of apopulation.To fully explore all possible causes of variation I am interested in avarietyof other factors that may affect communication behaviour. These includerangingpatterns, foraging behaviour and association patterns of dolphins.

Reactions to changes in the acoustic environment

While conspecifics certainly providevery relevant acoustic information to marine mammals, they areexposed to atremendous variety of different sound types. These can provideadditionalinformation about threats (e.g. predators) or opportunities (e.g.foraging). Weuse playback experiments to investigate communication distances andacousticmasking as well as reactions to other species or non-biological soundsources. These studies help us to understand what kind of information marine mammals extract from their acoustic environment and how they adjust their own calling behaviour to achieve optimal transmission of information. These studies also inform conservation efforts by giving details on howmarinemammals react to different kinds of noise.

My research encompasses a range of topics related to animal behaviour and evolution, particularly social learning, cultural evolution and niche construction, employing both experimental and theoretical approaches.

Current Projects

Niche Construction

Organisms construct and select important components of their environment, in the process affecting both the selection acting on themselves and their descendants, and the availability of resources to other organisms. We investigate niche construction using population genetics models and in an experimental marine invertebrate system.

Social Learning Strategies

Animals learn from others selectively according to evolved rules, called ‘social learning strategies’. This project investigates such strategies, through experimental studies in monkeys (capuchins, callitrichids), birds (budgerigars) and fish (sticklebacks), and through evolutionary game theory modelling.

Predicting the Diffusion and Inheritance of Behavioural Innovations

A challenge for social learning researchers is to identify animal ‘traditions’ and to work out how novel behaviour and skills spread. We use experimental studies of budgerigars and mathematical / statistical methods to determine where animals have acquired their behaviour through social learning, and how novel behaviour spreads in animal populations. The methods are applied to isolate ‘culture’ in natural animal populations, including chimpanzees and dolphins.

Intelligence and Brain Evolution in Primates

We conduct comparative statistical analyses exploring the correlates and causes of the large primate brain and the evolution of intelligence. Social learning, innovation and tool use all co-vary with primate relative brain size and may have been drivers of brain evolution.

MPhil/PhD project opportunities:

• Social learning strategies
• Predicting the diffusion and inheritance of behavioural innovations
• Intelligence and brain evolution in primates
• Niche construction

Anne with the model cormorant used to test the anti-predator response of piranhas.

Evolution of adaptive variation in fish communities; antipredator behaviour; speciation; species diversity and conservation of freshwater fish in the neotropics (Brazilian Amazon, Mexico and Trinidad) and UK.

Upper Aripo River, Trinidad

Much of my group's work is on the Trinidadian guppy, Poecilia reticulata, a species that has become a model system for investigating evolution in action. We are examining the evolution of reproductive isolation between fish in the Caroni and Oropouche drainages in Trinidad. These river systems have been separated for 1-2 million years. Although the guppies in them can still interbreed if given the opportunity, some post-mating reproductive barriers are already evident. For example, sperm from the female's own river system outcompete foreign sperm, and hybrid offspring formed when guppies from the two drainages are crossed are less viable than pure-bred fish. This research is being done with Anna Ludlow and Stephen Russell.

Northern Range, Trinidad.

Other investigations using the guppy concern aspects of mating behaviour (with Kit Magellan), the effect of thermal regime on behaviour and development (with Lars Pettersson), mutiple mating (with Alfredo Ojanguren) and interactions between guppies and their sister species Poecilia picta (with Indar Ramnarine of the University of the West Indies) .

Anne and Helder tagging piranhas prior to release back to the wild.

I am also interested in the evolution of schooling behaviour. Helder Queiroz (of the Mamirau· Sustainable Development Institute) and I are studying red-bellied piranhas, Pygocentrus nattereri, in the flooded forests of the Brazilian Amazon. Although piranhas are widely depicted as vicious, pack-hunting predators, in fact they are themselves preyed upon by river dolphins, caiman, piscivorous fish such as the pirarucu, and fish-eating birds including cormorants. Our work is showing that piranhas school as a defence against predation.
 

Esox lucius

In the UK I collaborate with Si‰n Grffiths (University of Cardiff), John Armstrong (FRS, Pitlochry) and Alfredo Ojanguren in a project on individual recognition and the benefits of associations between familiar groups of fish. We are using the European minnow, Phoxinus phoxinus, to test our ideas. The work is taking place in the artificial stream system at the Almondbank, FRS laboratory. A second project (with Lorraine Hawkins and John Armstrong) based at Almondbank is examining behavioural interactions between salmon, Salmo salar, and pike, Esox lucius - one of their most important natural predators.

My longstanding interest in the measurement of biological diversity and the structure of ecological assemblages is reflected in the recent publication of my book Measuring Biological Diversity.In addition, Peter Henderson (Pisces Conservation Ltd) and I are exploring changes in species abundance distributions over time.

Sigmoid display by male guppy.

Finally, I am interested in the conservation of biological diversity, particularly of freshwater fish assemblages. Constantino MacÌas Garcia (UNAM) and I are beginning to quantify the impact of introduced poeciliids on endangered fish in Mexico. I am continuing to investigate the biodiversity of freshwater assemblages in Trinidad with my colleagues there. Anuradha Bhat has recently joined the group. Her research is on fish assemblages in the Western Ghats region of India, one of the world's biodiversity hotspots. This will open up new challenges in biodiversity conservation.

My research interests are in parentage analysis, quantitative genetics, phenotypic evolution, sexual dimorphism, evolutionary genomics of plants, and societal applications of science

Research Group

Doctoral Students

• 2007-present  Ms Malin Rivers. Conservation status and conservation genetics of Delonix in Madagascar.
• 2003-2007 Dr. Mark Looseley. A Comparative investigation of nuclear DNA content and its phenotypic impacts in Silene marizii and S. latifolia. 
• 1994-2000 Dr. Jessica Wright . The effects of positive and negative selection on floral characters in natural population of Silene latifolia. Currently a Conservation Geneticist, USFS, University of California, Davis, CA, USA
• 1990-1997 Dr. Elizabeth Elle. Sex allocation and reproductive success in a perennial hermaphrodite, Solanum carolinense. Currently Associate Professor, Department of Biology, Simon Fraser University
• 1989-1995 Dr. Deborah Sheely . The ecological impact of genetic diversity on seedling recruitment in a tropical tree Campnosperma brevipetiolata (Anacardiaceae). Currently a Program Officer with USDA Competitive Grants.
• 1998-1993 Dr. Diane Byers . The genetic consequences of rarity in Eupatroium resinosum. Currently an Associate Professor at Illinois State University.

Postdoctoral Fellows

• 2005-2006 Dr. Rebecca Yahr , Ph.D. Duke University (advisors Dr. R. Vilgalys and Dr P. Depriest) population biology and genetics of lichen symbioses. Research Fellow, RBGE.
• 2000-2004 Dr. Christine Vassiliadis , Ph.D. University of Lille (advisors Dr. P. Vernet and Dr Saumitou-Laprade) evolution and maintenance of androdioecy. Lecturer, University of Orsay
• 1990-1994 Dr. Denise E Costich , Ph.D. University of Iowa (advisor, Dr. H. F. Howe) evolution of dioecy in plants. Cornell University/Boyce Thompson Institute
• 1989 Dr. Lynda F. Delph . Ph.D. University of Canterbury, New Zealand (advisor Dr. D. G. Lloyd) gender specific resource allocation in plants Associate Professor, Indiana University.

Parentage analysis & quantitative genetics

I have a long-standing interest in the application of statistical methods of genealogical inference to the analysis of the structure and genetic dynamics of natural populations. Applying likelihood methods that originated in forensic analysis of human paternity, the assignment of male parentage in plant populations provides information on gene flow and impacts of specific phenotypic traits on male reproductive success. Specific contributions in this area have included development of likelihood models for paternity analysis, application of such models to understating the structure of a range of plant populations, and the delelopment of a Windows-based software package, PatQuest, for conducting such analyses. Present work in this area includes development of statistical methods for the integration of likelihood-based paternity inference with REML estimation of quantitative genetic parameters, to be applied to natural populations where standard multigenerational quantitative genetics experiments are not practical. In addition, models for investigating gene flow, based on approaches derived from paternity analyses, have been applied to investigation of gene flow in transgenic cultivars.

• Meagher TR (1986) Analysis of paternity within a natural population of Chamaelirium luteum . I. Identification of most-likely male parents. American Naturalist . 128: 199-215.
• Meagher TR, Thompson EA. (1987) Identification of parentage for seedlings within a natural population of Chamaelirium luteum . Ecology 68: 803-812.
• Thompson EA, Meagher TR (1998) Genome sharing and the estimation of pairwise relationship. Theoretical and Applied Genetics 97: 857-864.
• Smouse PE, Meagher TR, Kobak CJ (1999) Parentage analysis in Chamaelirium luteum (L.) Gray (Liliaceae): why do some males have disproportionate reproductive contributions. Journal of Evolutionary Biology 12: 1069-1077.
• Elle E, Meagher TR (2000) Sex allocation and reproductive success in the andromonoecious perennial, Solanum carolinense (Solanaceae). II. Paternity and functional gender. American Naturalist 156: 622-636.
• MeagherTR, Vassiliadis C (2003) Spatial geometry determines gene flow in plant populations. Hails RS, Beringer JE, Godfray HCJ (eds.) Genes in the environment. Pp. 76-90.
  Oxford, UK, Blackwell Science Ltd. Meagher T., Belanger FC, Day PR (2003) Using empirical data to model transgene dispersal. Trans. Royal Society (London) B 358: 1157-1162.

Sexual dimorphism and sex-specific selection

Reproductive success as male or female parents in plants is based on very different pathways, subject to sex-specific processes of selection. In dioecious species, long-term consequences of such sex-specific selection can lead to sexual dimporphism in a wide range of traits, from the molecular level to the ecological. My interest in this area began with an investigation of resource allocation and life history impacts of such in Chamaelirium luteum (Liliaceae, pictured above), a flowering plant that exhibits extreme sexual dimorphism in inflorescence structure. More recent work on this phenomenon has focused on floral dimorphism in the dioecious Silene latifolia , which has a well-established genetic basis for sex determination, and a shorter life-span that is more amenable to genetic investigation.

• Meagher TR (1984) Sexual dimorphism and ecological differentiation of male and female plants. Annals Missouri Botanical Garden 71: 254-264.
• Meagher TR (1994) The quantitative genetics of sexual dimorphism in Silene latifolia . II. Responses to sex-specific selection. Evolution 48: 939-951.
• Delph LF, Meagher TR (1995) Sexual dimorphism masks life history trade-offs in the dioecious plant Silene latifolia . Ecology 76: 775-785.
• Meagher TR, Delph LF (2001) Individual flower demography, floral phenology, and life history in Silene latifolia . Evolutionary Ecology Research 3: 845-860.
• Costich DC, Meagher TR (2001) Impacts of floral gender and whole-plant gender on floral evolution in Ecballium elaterium (Cucurbitaceae). Biological Journal of the Linnean Society 74: 475-487.
• Wright JW, Meagher TR (2004) Selection on floral characters of natural Spanish populations of Silene latifolia . Journal of Evolutionary Biology , in press.
   

Evolutionary genomics and phenotypic evolution

My investigations into the genetic basis of floral dimorphism in flower size in Silene latifolia have inexorably led to a more detailed analysis of the genetic basis of flower size in general. As this is a quantitative trait, initial investigations involved quantitative genetics approaches. More recently, a link has been established between quantitative variation in flower size and genome size/organization. This latter discovery has led to a phylogenetic investigation of the relationship between genome size and flower size evolution across related taxa, and a joint QTL analysis of flower size and DNA content.

Present work in this area is exploring the possible role of specific repetitive sequences, such as retrotransposons, in DNA content variation associated with flower size evolution. We are also investigation the role of such DNA content variation in contributing to reproductive isolation between species.

• Meagher TR, Costich DE (1994) Sexual dimorphism in nuclear DNA content within and between populations of Silene latifolia . American Journal of Botany 81: 1198-1204.
• Meagher TR, Costich DE (1996) Nuclear DNA content and floral evolution.Proceedings of the Royal Society (London), Series B 263: 1455-1460.
• Meagher TR (1999) The quantitative genetics of sexual dimorphism. In Sexual dimorphism in plants , M. Geber, T. Dawson, and L. Delph, eds. Springer-Verlag New York.

Societal applications of science

Science is conducted within a broader societal context, and indeed is based on support derived from that context in the form of government financing. As a practicing scientist, one has an obligation to identify connections between basic research and potential application to societal needs. My activities in this area have been several fold. First, I have applied methods of paternity analysis and other analytical tools from evolutionary biology to the issue of gene flow from transgenic cultivars to adjacent ruderal populations. On a science policy level, I was a co-chair of a US national initiative on Evolution, Science and Society, which was directed towards outlining the importance of scientific contributions of evolutionary biology, I have served as a founding and current member of the Society for the Study of Evolution 's Education Committee, and I am presently a member of the Science Advisory Council of the UK Department of Environment, Food and Rural Affairs.

• Meagher TR (1999) Evolution and today's society. BioScience 49: 923-925.
• Meagher TR, Futuyma DJ (eds) (2001) Evolution, Science and Society: evolutionary biology and the national research agenda. California Journal of Science Education 1: 19-32.
• Meagher TR, Futuyma DJ (2001) Executive document: Evolution, science, and society - Foreword: Evolution in the century of biology. American Naturalist 158: 1-46 Suppl. S.
   

Overview of Research Interests:

The Ritchie laboratory takes a broad approach to studies of the origin of species. Behaviours involved in sexual isolation are characterised and their genetic control studied, using both quantitative and molecular approaches to behaviour genetics, as well as phylogeographic studies of variation in behaviour. 

Current Research Projects:

Analysing genes influencing Drosophila behaviour

We have used Quantitative Trait Locus techniques to localise the genomic location of genes influencing behaviour in flies. Now that several genomes are available, it is possible to move into ‘postgenomic’ studies of patterns in the evolution of these genes, and to begin looking at the expression and variation of candidate genes

Variation in female mate preferences

Female preferences are very important to sexual selection and speciation, but are difficult to measure and quantify. We measure preference variation in different species of Drosophila and other insects such as bushcrickets.

Phylogeography and behaviour

Studies of geographic variation in a range of organisms, including Mexican fish and cannibalistic crickets, explore the importance of variation in behaviour to population genetic structure and the role of sexual selection in speciation.

MPhil/PhD project opportunities:

Please contact me directly to discuss potential postgraduate opportunities.

A. Environmental Physiology of Invertebrates.

Water balance and osmoregulation in insects. Thermal physiology in relation to microclimate and behaviour, especially in bees and other terrestrial and littoral invertebrates.

B. Insect-Plant Interactions.

Pollination ecology. Interactions between pollinators, pests and predators.

Insects as pests on crop plants, and interactions with crop microclimates. Ant deterrence in flowers.

C. Animal behaviour, especially social insects.

Ecology and behaviour of insects, specifically insect-plant interactions and pollination ecology. The constraints acting on pollinators, especially bees, in temperate and arid systems.

D. Invertebrate Evolution and Convergent Evolution.

Invertebrate morphology and fossils; the evolution of basic body plans, and the prevalence of convergent evolution; implications for phylogenetic approaches.