Holocene vegetation, fire and climate interactions on the westernmost fringe of the Mediterranean Basin

Quaternary Science Reviews

Volumn 59, Issue , 2013, Pages 5-17

  Morales Molino, César ^a,b   García Antón, Mercedes ^b   Postigo Mijarra, José M ^a   Morla, Carlos ^a  

^a UNIVERSIDAD POLITÉCNICA DE MADRID   (Spain)

^b UNIVERSIDAD AUTÓNOMA DE MADRID   (Spain)

Author keywords

Betula; Charcoal; Fire ecology; Forest management; Heathlands; Macrofossils; Pollen; Spain

Indexed keywords

BETULA; FIRE ECOLOGY; HEATHLANDS; MACROFOSSILS; POLLEN; SPAIN;

CHARCOAL; CONSERVATION; FIRES; SECONDARY RECOVERY; VEGETATION;

FORESTRY;

BOREAL FOREST; CHARCOAL; CONIFEROUS FOREST; FIRE HISTORY; FOREST FIRE; FOREST MANAGEMENT; FOSSIL RECORD; GRASSLAND; HEATHLAND; HOLOCENE; HUMAN ACTIVITY; PALEOECOLOGY; PALYNOLOGY; REPLACEMENT; SECONDARY SUCCESSION; SHRUBLAND; VEGETATION COVER; BASIN; CLIMATE CHANGE; MATURATION; MEDITERRANEAN ENVIRONMENT; MOUNTAIN REGION; SUCCESSION; TEMPERATE ENVIRONMENT; TRANSGRESSION; VEGETATION;

BASINS; BETULA; CHARCOAL; CONSERVATION; FOREST FIRES; FOSSILS; PLANTS; POLLEN; SPAIN; FIRES; FOREST MANAGEMENT; FORESTRY; RECOVERY;

IBERIAN CORDILLERA; MEDITERRANEAN REGION; MEDITERRANEAN SEA; SPAIN; CENTRAL IBERIAN ZONE;

BETULA; PINUS PINASTER; PINUS SYLVESTRIS;

EID: 84870179649     PISSN: 02773791     EISSN: None     Source Type: Journal    
DOI: 10.1016/j.quascirev.2012.10.027     Document Type: Article

References (93)

1. Anderson R.S., Jiménez-Moreno G., Carrión J.S., Pérez-Martínez C. Postglacial history of alpine vegetation, fire, and climate from Laguna de Río Seco, Sierra Nevada, southern Spain. Quaternary Science Reviews 2011, 30:1615-1629.
2. Allen J.R.M., Huntley B., Watts W.A. The vegetation and climate of northwest Iberia over the last 14000 yr. Journal of Quaternary Science 1996, 11:125-147.
3. Álvarez-Sanchís J.R. The Iron Age in western Spain (800 BC-AD 50): an overview. Oxford Journal of Archaeology 2000, 19:65-89.
4. Arrieta S., Suárez F. Spatial patterns of seedling emergence and survival as a critical phase in holly (Ilex aquifolium L.) woodland recruitment in Central Spain. Forest Ecology and Management 2005, 205:267-282.
5. Atkinson M.D. Biological flora of the British Isles 175: Betula pendula Roth (B. verrucosa Ehrh.) and B. pubescens Ehrh. Journal of Ecology 1992, 80:837-870.
6. Bartolomé C., álvarez J., Vaquero J., Costa M., Casermeiro M.A., Giraldo J., Zamora J. Los tipos de hábitat de interés comunitario de España; guía básica 2005, Dirección General de la Biodiversidad, Ministerio de Medio Ambiente, Madrid, 287 pp.
7. Bennett K.D. Determination of the number of zones in a biostratigraphical sequence. New Phytologist 1996, 132:155-170.
8. Bennett K.D. Documentation for Psimpoll 4.27 and Pscomb 1.03. C Programs for Plotting and Analyzing Pollen Data 2009, The 14Chrono Centre, Archaeology and Palaeoecology, Queen's University of Belfast, Belfast, UK, Available at:, (accessed 20.09.09.). http://www.chrono.qub.ac.uk/psimpoll/psimpoll.html.
9. Birks H.H. Plant macrofossils. Tracking Environmental Change Using Lake Sediments Volume 3: Terrestrial, Algal and Siliceous Indicators 2001, 49-74. Kluwer Academic Publishers, Dordrecht, The Netherlands. J.P. Smol, H.J.B. Birks, W.M. Last (Eds.).
10. Bunting M.J. Detecting woodland remnants in cultural landscapes: modern pollen deposition around small woodlands in northwest Scotland. Holocene 2002, 12:291-301.
11. Carrión J.S. Patterns and processes of Late Quaternary environmental change in a mountain region of southwestern Europe. Quaternary Science Reviews 2002, 21:2047-2066.
12. Carrión J.S., Sánchez-Gómez P., Mota J.F., Yll R., Chaín C. Holocene vegetation dynamics, fire and grazing in the Sierra de Gádor, southern Spain. The Holocene 2003, 13:839-849.
13. Carrión J.S., Fuentes N., González-Sampériz P., Sánchez Quirante L., Finlayson J.C., Fernández S., Andrade A. Holocene environmental change in a montane region of southern Europe with a long history of human settlement. Quaternary Science Reviews 2007, 26:1455-1475.
14. Carrión J.S., Fernández S., González-Sampériz P., Gil-Romera G., Badal E., Carrión-Marco Y., López-Merino L., López-Sáez J.A., Fierro E., Burjachs F. Expected trends and surprises in the Lateglacial and Holocene vegetation history of the Iberian Peninsula and Balearic Islands. Review of Palaeobotany and Palynology 2010, 162:458-475.
15. Castroviejo Riqueza florística de la peninsula Ibérica e islas Baleares. El proyecto 'Flora Iberica'. La diversidad biológica de España 2002, 167-174. Prentice Hall, Madrid. F.D. Pineda, J.M. de Miguel, M. Casado, J. Montalvo (Eds.).
16. Colombaroli D., Vannière B., Chapron E., Magny M., Tinner W. Fire-vegetation interactions during the Mesolithic-Neolithic transition at Lago dell'Accesa, Tuscany, Italy. Holocene 2008, 18:679-692.
17. Connor S.E., Araújo J., van der Knaap W.O., van Leeuwen J.F.N. A long-term perspective on biomass burning in the Serra da Estrela, Portugal. Quaternary Science Reviews 2012, 55:114-124.
18. Corella J.P., Moreno A., Morellón M., Rull V., Giralt S., Rico M.T., Pérez-Sanz A., Valero-Garcés B.L. Climate and human impact on a meromictic lake during the last 6000 years (Montcortès Lake, Central Pyrenees, Spain). Journal of Paleolimnology 2011, 46:351-367.
19. Los bosques ibéricos: Una interpretación geobotánica 1997, Planeta, Barcelona. M. Costa, C. Morla, H. Sáinz (Eds.).
20. Davis B.A.S., Brewer S., Stevenson A.C., Guiot J., Data Contributors The temperature of Europe during the Holocene reconstructed from pollen data. Quaternary Science Reviews 2003, 22:1701-1716.
21. Faegri K., Iversen J. Textbook of Pollen Analysis 1989, Wiley, Chichester, UK. fourth ed.
22. Finsinger W., Tinner W. Minimum count sums for charcoal concentration estimates in pollen slides: accuracy and potential errors. The Holocene 2005, 15:293-297.
23. Fletcher W.J., Boski T., Moura D. Palynological evidence for environmental and climatic change in the lower Guadiana valley, Portugal, during the last 13000 years. Holocene 2007, 481-494.
24. Franco Múgica F. El análisis polínico en la reconstrucción del paisaje vegetal. Los bosques de Gredos a través del tiempo. Monografías de la Red de Espacios Naturales de Castilla y León, serie técnica 2009, 89-117. Junta de Castilla y León, Valladolid. M. Génova, F. Gómez Manzaneque, C. Morla (Eds.).
25. Franco Múgica F., García Antón M., Sáinz Ollero H. Vegetation dynamics and human impact in the Sierra de Guadarrama, Central System, Spain. The Holocene 1998, 8:69-82.
26. Franco Múgica F., García Antón M., Maldonado J., Morla C., Sáinz Ollero H. The Holocene history of Pinus forests in the Spanish Northern Meseta. The Holocene 2001, 11:343-358.
27. Franco-Múgica F., García-Antón M., Maldonado-Ruiz J., Morla-Juaristi C., Sáinz-Ollero H. Ancient pine forest on inland dunes in the Spanish northern Meseta. Quaternary Research 2005, 63:1-14.
28. García-Antón M., Franco-Múgica F., Morla-Juaristi C., Maldonado-Ruiz J. The biogeographical role of Pinus forests on the Northern Spanish Meseta: a new Holocene sequence. Quaternary Science Reviews 2011, 30:757-768.
29. Gil-Romera G., Carrión J.S., Pausas J.G., Sevilla-Callejo M., Lamb H.F., Fernández S., Burjachs F. Holocene fire activity and vegetation response in South-Eastern Iberia. Quaternary Science Reviews 2010, 29:1082-1092.
30. González-Sampériz P., Valero-Garcés B.L., Moreno A., Jalut G., García-Ruiz J.M., Martí-Bono C., Delgado-Huertas A., Navas A., Otto T., Dedoubat J.J. Climate variability in the Spanish Pyrenees during the last 30,000 yr revealed by the El Portalet sequence. Quaternary Research 2006, 66:38-52.
31. González-Sampériz P., Valero-Garcés B.L., Moreno A., Morellón M., Navas A., Machín J., Delgado-Huertas A. Vegetation changes and hydrological fluctuations in the Central Ebro Basin (NE Spain) since the Late Glacial period: saline lake records. Palaeogeography, Palaeoclimatology, Palaeoecology 2008, 259:157-181.
32. Grimm E.C. A Fortran 77 program for stratigraphically constrained cluster analysis by the method of incremental sum of squares. Computer Geosciences 1987, 13:13-35.
33. Heegard E., Birks H.J.B., Telford R.J. Relationships between calibrated ages and depth in stratigraphical sequences: an estimation procedure by mixed-effect regression. The Holocene 2005, 15:612-618.
34. Hernández L., Rubiales J.M., Morales-Molino C., Romero F., Sanz C., Gómez Manzaneque F. Reconstructing forest history from archaeological data: a case study in the Duero basin assessing the origin of controversial forests and the loss of tree populations of great biogeographical interest. Forest Ecology and Management 2011, 261:1178-1187.
35. Higuera P.E., Brubaker L.B., Anderson P.M., Hu F.S., Brown T.A. Vegetation mediated the impacts of postglacial climate change on fire regimes in the south-central Brooks Range, Alaska. Ecological Monographs 2009, 79:201-219.
36. 14C data for carbon cycle modelling and age calibration purposes. Radiocarbon 2004, 46:1273-1298.
37. Jalut G., Turu i Michels V., Dedoubat J.J., Otto T., Ezquerra J., Fontugne M., Belet J.M., Bonnet L., García de Celis A., Redondo-Vega J.M., Vidal-Romaní J.R., Santos L. Palaeoenvironmental studies in NW Iberia (Cantabrian range): Vegetation history and synthetic approach of the last deglaciation phases in the western Mediterranean. Palaeogeography, Palaeoclimatology, Palaeoecology 2010, 297:330-350.
38. Jiménez-Moreno G., Anderson R.S. Holocene vegetation and climate change recorded in alpine bog sediments from Borreguiles de la Virgen, Sierra Nevada, southern Spain. Quaternary Research 2012, 77:44-53.
39. Kutzbach J.E., Webb T. Conceptual basis for understanding Late-Quaternary climates. Global Climates since the Last Glacial Maximum 1993, 5-11. University of Minnesota Press, Minneapolis. H.E. Wright, J.E. Kutzbach, T. Webb, W.F. Ruddiman, F.A. Street-Perrott, P.J. Bartlein (Eds.).
40. López-Merino L., López-Sáez J.A., Alba-Sánchez F., Pérez-Díaz S., Carrión J.S. 2000 years of pastoralism and fire shaping high-altitude vegetation of Sierra de Gredos in central Spain. Review of Palaeobotany and Palynology 2009, 158:42-51.
41. Macaya J. Estudio geológico estructural de la Sierra de Francia (provincia de Salamanca y Cáceres). Cuadernos de Geología Ibérica 1981, 7:567-576.
42. Magny M., Vannière B., Calò C., Millet L., Leroux A., Peyron O., Zanchetta G., La Mantia T., Tinner W. Holocene hydrological changes in south-western Mediterranean as recorded by lake-level fluctuations at Lago Preola, a coastal lake in southern Sicily, Italy. Quaternary Science Reviews 2011, 30:2459-2475.
43. Maldonado, J., 1994. Evolución Tardiglaciar y Holocena de la vegetación en los macizos del Noroeste Peninsular. PhD dissertation, Universidad Politécnica de Madrid, Madrid.
44. Maliouchenko O., Palmé A.E., Buonamici A., Vendramin G.G., Lascoux M. Comparative phylogeography and population structure of European Betula species, with particular focus on B. pendula and B. pubescens. Journal of Biogeography 2007, 34:1601-1610.
45. Mayewski P.A., Rohling E.E., Stager J.C., Karlén W., Maasch K.A., Meeker L.D., Meyerson E.A., Gasse F., van Kreveld S., Holmgren K., Lee-Thorp J., Rosqvist G., Rack F., Staubwasser M., Schneider R.R., Steig E.J. Holocene climate variability. Quaternary Research 2004, 62:243-255.
46. Moore P.D., Webb J.A., Collinson M.E. Pollen Analysis 1991, Blackwell Scientific Publications, Oxford, UK.
47. Morales-Molino C., García Antón M., Morla C. Late Holocene vegetation dynamics on an Atlantic-Mediterranean mountain in NW Iberia. Palaeogeography, Palaeoclimatology, Palaeoecology 2011, 302:323-337.
48. Morales-Molino C., Postigo-Mijarra J.M., Morla C., García-Antón M. Long-term persistence of Mediterranean pine forests in the Duero Basin (central Spain) during the Holocene: the case of Pinus pinaster Aiton. Holocene 2012, 22:561-570.
49. Morellón M., Valero-Garcés B., Moreno A., González-Sampériz P., Mata P., Romero O., Maestro M., Navas A. Holocene palaeohydrology and climate variability in northeastern Spain: the sedimentary record of Lake Estanya (Pre-Pyrenean range). Quaternary International 2008, 181:15-31.
50. Moreno A., López-Merino L., Leira M., Marco-Barba J., González-Sampériz P., Valero-Garcés B.L., López-Sáez J.A., Santos L., Mata P., Ito E. Revealing the last 13,500 years of environmental history from the multiproxy record of a mountain lake (Lago Enol, northern Iberian Peninsula). Journal of Paleolimnology 2011, 46:327-349.
51. Moreno A., Pérez A., Frigola J., Nieto-Moreno V., Rodrigo-Gámiz M., Martraf B., González-Sampériz P., Morellón M., Martín-Puertas C., Corella J.P., Belmonte Á., Sancho C., Cacho I., Herrera G., Canals M., Grimalt J.O., Jiménez-Espejo F., Martínez-Ruiz F., Vegas-Vilarrùbia T., Valero-Garcés B.L. The Medieval Climate Anomaly in the Iberian Peninsula reconstructed from marine and lake records. Quaternary Science Reviews 2012, 43:16-32.
52. Muñoz Sobrino C., Ramil-Rego P., Rodríguez Guitián M. Upland vegetation in the north-west Iberian Peninsula after the last glaciation: forest history and deforestation dynamics. Vegetation History and Archaeobotany 1997, 6:215-233.
53. Muñoz Sobrino C., Ramil-Rego P., Rodríguez Guitián M.A. Vegetation in the mountains of northwest Iberia during the Last Glacial-Interglacial transition. Vegetation History and Archaeobotany 2001, 10:7-21.
54. Oswald W.W., Anderson P.M., Brown T.A., Brubaker L.B., Hu F.S., Lozhkin A.V., Tinner W., Kaltenrieder P. Effects of sample mass and macrofossil type on radiocarbon dating of arctic and boreal lake sediments. The Holocene 2005, 15:758-767.
55. Pantaleón-Cano J., Yll E.I., Pérez-Obiol R., Roure J.M. Palynological evidence for vegetational history in semi-arid areas of the western Mediterranean (Almería, Spain). Holocene 2003, 13:109-119.
56. Parshall T., Calcote R. Effect of pollen from regional vegetation on stand-scale forest reconstruction. The Holocene 2001, 11:81-87.
57. Pausas J.G., Verdú M. Plant persistence traits in fire-prone ecosystems of the Mediterranean basin: a phylogenetic approach. Oikos 2005, 109:196-202.
58. Peñalba M.C. The history of the Holocene vegetation in northern Spain from pollen analysis. Journal of Ecology 1994, 82:815-832.
59. Peñalba M.C., Maurice A., Guiot J., Duplessy J.C., de Beaulieu J.L. Termination of the Last glaciation in the Iberian Peninsula inferred from the pollen sequence of Quintanar de la Sierra. Quaternary Research 1997, 48:205-214.
60. Punt, W. et al., 1976-2009. The Northwest European Pollen Flora, vol. I (1976), vol. II (1980), vol. III (1981), vol. IV (1984), vol. V (1988), vol. VI (1991), vol. VII (1996), vol. VIII (2003), vol. IX (2009). Elsevier, Amsterdam.
61. Reed J.M., Stevenson A.C., Juggins S. A multi-proxy record of Holocene climatic change in southwest Spain: the Laguna de Medina, Cádiz. Holocene 2001, 11:707-719.
62. Reille M. Pollen et Spores d'Europe et d'Afrique Du Nord 1992, Laboratoire de botanique historique et palynologie, Marseille, France.
63. Reille M. Pollen et Spores d'Europe et d'Afrique Du Nord, Supplement 1 1995, Laboratoire de botanique historique et palynologie, Marseille, France.
64. Reimer P.J., Baillie M.G.L., Bard E., Bayliss A., Beck J.W., Blackwell P.G., Bronk Ramsey C., Buck C.E., Burr G.S., Edwards R.L., Friedrich M., Grootes P.M., Guilderson T.P., Hajdas I., Heaton T.J., Hogg A.G., Hughen K.A., Kaiser K.F., Kromer B., McCormac F.G., Manning S.W., Reimer R.W., Richards D.A., Southon J.R., Talamo S., Turney C.S.M., van der Plicht J., Weyhenmeyer C.E. INTCAL09 and MARINE09 radiocarbon age calibration curves, 0-50,000 years cal. BP. Radiocarbon 2009, 51:1111-1150.
65. Rendell S., Ennos R.A. Chloroplast DNA diversity of the dioecious European tree Ilex aquifolium L. (English holly). Molecular Ecology 2003, 12:2681-2688.
66. Renssen H., Seppä H., Heiri O., Roche D.M., Goosse H., Fichefet T. The spatial and temporal complexity of the Holocene thermal maximum. Nature Geoscience 2009, 2:411-414.
67. Rius D., Vannière B., Galop D., Richard H. Holocene fire regime changes from multiple-site sedimentary charcoal analyses in the Lourdes basin (Pyrenees, France). Quaternary Science Reviews 2011, 30:1696-1709.
68. Roberts N., Brayshaw D., Kuzucuoglu C., Pérez R., Sadori L. The mid-Holocene climatic transition in the Mediterranean: causes and consequences. Holocene 2011, 21:3-13.
69. Rubiales J.M., García-Amorena I., Génova M., Gómez Manzaneque F., Morla C. The Holocene history of highland pine forests in a submediterranean mountain: the case of Gredos mountain range (Iberian Central range, Spain). Quaternary Science Reviews 2007, 26:1759-1770.
70. Rubiales J.M., García-Amorena I., García álvarez S., Gómez Manzaneque F. The Late Holocene extinction of Pinus sylvestris in the western Cantabrian Range (Spain). Journal of Biogeography 2008, 35:1840-1850.
71. Rubiales J.M., García-Amorena I., Hernández L., Génova M., Martínez F., Gómez Manzaneque F., Morla C. Late Quaternary dynamics of pinewoods in the Iberian Mountains. Review of Palaeobotany and Palynology 2010, 162:476-491.
72. Rubiales J.M., Morales-Molino C., García álvarez S., García-Antón M. Negative responses of highland pines to anthropogenic activities in inland Spain: a palaeoecological perspective. Vegetation History and Archaeobotany 2011, 21:397-412.
73. Ruiz de la Torre J. Mapa Forestal de España: hoja 3-6 Plasencia 1990, ICONA-Ministerio de Agricultura, Pesca y Alimentación, Madrid.
74. Ruiz del Árbol M., Sánchez-Palencia F.J. La minería aurífera romana en el noreste de Lusitania: Las Cavenes de El Cabaco (Salamanca). Archivo Español de Arqueología 1999, 72:119-139.
75. Salvo E. Guía de helechos de la Península Ibérica y Baleares 1990, Ed. Pirámide, Madrid.
76. Schweingrüber F.H. Anatomy of European Woods 1990, Paul Haupt Verlag, Bern.
77. Stockmarr J. Tablets with spores used in absolute pollen analysis. Pollen et Spores 1971, 13:615-621.
78. Stuiver M., Reimer P.J. Extended 14C database and revised CALIB radiocarbon calibration program. Radiocarbon 1993, 35:215-230. CALIB 6.0 radiocarbon calibration program is available online on:. http://intcal.qub.ac.uk/calib/.
79. Sugita S. Pollen representation of vegetation in Quaternary sediments: theory and method in patchy vegetation. Journal of Ecology 1994, 82:881-897.
80. Telford R.J., Heegaard E., Birks H.J.B. The intercept is a poor estimate of a calibrated radiocarbon age. The Holocene 2004, 14:296-298.
81. Thorndycraft V.R., Benito G. The Holocene fluvial chronology of Spain: evidence from a newly compiled radiocarbon database. Quaternary Science Reviews 2006, 25:223-234.
82. Tinner W., Hu F.S. Size parameters, size-class distribution and area-number relationship of microscopic charcoal: relevance for fire reconstruction. The Holocene 2003, 13:499-505.
83. Tinner W., Conedera M., Ammann B., Gaggeler H.W., Gedye S., Jones R., Sagesser B. Pollen and charcoal in lake sediments compared with historically documented forest fires in southern Switzerland since AD 1920. The Holocene 1998, 8:31-42.
84. Tinner W., van Leeuwen J.F.N., Colombaroli D., Vescovi E., van der Knaap W.O., Henne P.D., Pasta S., D'Angelo S., La Mantia T. Holocene environmental and climatic changes at Gorgo Basso, a coastal lake in southern Sicily, Italy. Quaternary Science Reviews 2009, 28:1498-1510.
85. Valbuena L., Vera M.L. The effects of thermal scarification and seed storage on germination of four heathland species. Plant Ecology 2002, 161:137-144.
86. Valbuena-Carabaña M., López de Heredia U., Fuentes-Utrilla P., González-Doncel I., Gil L. Historical and recent changes in the Spanish forests: a socio-economic process. Review of Palaeobotany and Palynology 2010, 162:492-506.
87. Valsecchi V., Carraro G., Conedera M., Tinner W. Late-Holocene vegetation and land-use dynamics in the Southern Alps (Switzerland) as a basis for nature protection and forest management. Holocene 2010, 20:483-495.
88. van der Knaap W.O., van Leeuwen J.F.N. Holocene vegetation succession and degradation as responses to climatic change and human activity in the Serra da Estrela, Portugal. Review of Palaeobotany and Palynology 1995, 89:153-211.
89. van der Knaap W.O., van Leeuwen J.F.N. Late Glacial and early Holocene vegetation succession, altitudinal vegetation zonation, and climatic change in the Serra da Estrela, Portugal. Review of Palaeobotany and Palynology 1997, 97:239-285.
90. Vannière B., Power M.J., Roberts N., Tinner W., Carrión J., Magny M., Bartlein P., Colombaroli D., Daniau A.L., Finsinger W., Gil-Romera G., Kaltenrieder P., Pini R., Sadori L., Turner R., Valsecchi V., Vescovi E. Circum-Mediterranean fire activity and climate changes during the mid-Holocene environmental transition (8500-2500 cal. BP). Holocene 2011, 21:53-73.
91. Vescovi E., Ravazzi C., Arpenti E., Finsinger W., Pini R., Valsecchi V., Wick L., Ammann B., Tinner W. Interactions between climate and vegetation during the Lateglacial period as recorded by lake and mire sediment archives in Northern Italy and Southern Switzerland. Quaternary Science Reviews 2007, 26:1650-1669.
92. Whitlock C., Larsen C. Charcoal as a fire proxy. Terrestrial, Algal and Siliceous Indicators 2001, vol. 3:75-97. Kluwer Academic Publishers, Dordrecht, The Netherlands. J.P. Smol, H.J.B. Birks, W.M. Last (Eds.).
93. Willis K.J., Birks H.J.B. What is natural? The need for a long-term perspective in biodiversity conservation. Science 2006, 314:1261-1265.