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Be like and the Constant Rate Effect: from the bottom to the top of the S-curve
- MATT HUNT GARDNER, DEREK DENIS, MARISA BROOK, SALI A. TAGLIAMONTE
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- Journal:
- English Language & Linguistics / Volume 25 / Issue 2 / June 2021
- Published online by Cambridge University Press:
- 21 April 2020, pp. 281-324
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The be like quotative emerged rapidly around the English-speaking world and has quickly saturated the quotative systems of young speakers in multiple countries. We study be like (and its covariants) in two communities – Toronto, Canada, and York, United Kingdom – in apparent time and at two separate points in real time. We trace the apparent-time trajectory of be like and its covariants from inception to saturation. We take advantage of the prodigious size of our dataset to examine understudied aspects of the linguistic factors that condition quotative variation. Building on earlier suggestions (Cukor-Avila 2002; Durham et al.2012) that be like might show patterning over time consistent with the Constant Rate Effect (or CRE, Kroch 1989), we argue that the CRE does indeed apply to the rise of be like, but needs to be handled with care. Logistic modelling assumes that the top of the S-curve is located at 100 per cent of a given variable context. In the case of be like, the saturation point is nearer 75–85 per cent, with minor variants retaining small semantic footholds in the system. In conjunction with our analysis, we suggest how to adapt the predictions of the CRE to changes likely to lead to saturation but not categorical use.
Peaks and arrowheads of vernacular reorganization
- Derek Denis, Matt Hunt Gardner, Marisa Brook, Sali A. Tagliamonte
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- Journal:
- Language Variation and Change / Volume 31 / Issue 1 / March 2019
- Published online by Cambridge University Press:
- 02 May 2019, pp. 43-67
- Print publication:
- March 2019
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A key component of Labov's (2001:411) socially motivated projection model of language change is the hypothesis that adolescents and preadolescents undergo a process of vernacular reorganization, which leads to a “seamless” progression of changes in progress. Between the ages of approximately five and 17, children and adolescents increase the “frequency, extent, scope, or specificity” of changes in progress along the community trajectory (Labov, 2007:346). Evidence of advancement via vernacular reorganization during this life stage has come from peaks in the apparent-time trajectory of a change around the age of 17 (e.g., Labov, 2001; Tagliamonte & D'Arcy, 2009). However, such peaks do not rule out the alternative explanations of retrograde change or age-grading. This paper presents both apparent time and real-time evidence for vernacular reorganization. We observe the arrowhead formation—a counterpart of the adolescent peak—for quotative be like in a trend study of adolescents and young adults in Toronto, Canada. Our results rule out the alternative explanations for previously observed adolescent peaks.
Psychosocial functioning among regular cannabis users with and without cannabis use disorder
- Katherine T. Foster, Brooke J. Arterberry, William G. Iacono, Matt McGue, Brian M. Hicks
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- Journal:
- Psychological Medicine / Volume 48 / Issue 11 / August 2018
- Published online by Cambridge University Press:
- 27 November 2017, pp. 1853-1861
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Background
In the United States, cannabis accessibility has continued to rise as the perception of its harmfulness has decreased. Only about 30% of regular cannabis users develop cannabis use disorder (CUD), but it is unclear if individuals who use cannabis regularly without ever developing CUD experience notable psychosocial impairment across the lifespan. Therefore, psychosocial functioning was compared across regular cannabis users with or without CUD and a non-user control group during adolescence (age 17; early risk) and young adulthood (ages 18–25; peak CUD prevalence).
MethodWeekly cannabis users with CUD (n = 311), weekly users without CUD (n = 111), and non-users (n = 996) were identified in the Minnesota Twin Family Study. Groups were compared on alcohol and illicit drug use, psychiatric problems, personality, and social functioning at age 17 and from ages 18 to 25. Self-reported cannabis use and problem use were independently verified using co-twin informant report.
ResultsIn both adolescence and young adulthood, non-CUD users reported significantly higher levels of substance use problems and externalizing behaviors than non-users, but lower levels than CUD users. High agreement between self- and co-twin informant reports confirmed the validity of self-reported cannabis use problems.
ConclusionsEven in the absence of CUD, regular cannabis use was associated with psychosocial impairment in adolescence and young adulthood. However, regular users with CUD endorsed especially high psychiatric comorbidity and psychosocial impairment. The need for early prevention and intervention – regardless of CUD status – was highlighted by the presence of these patterns in adolescence.
Education in Twins and Their Parents Across Birth Cohorts Over 100 years: An Individual-Level Pooled Analysis of 42-Twin Cohorts
- Karri Silventoinen, Aline Jelenkovic, Antti Latvala, Reijo Sund, Yoshie Yokoyama, Vilhelmina Ullemar, Catarina Almqvist, Catherine A. Derom, Robert F. Vlietinck, Ruth J. F. Loos, Christian Kandler, Chika Honda, Fujio Inui, Yoshinori Iwatani, Mikio Watanabe, Esther Rebato, Maria A. Stazi, Corrado Fagnani, Sonia Brescianini, Yoon-Mi Hur, Hoe-Uk Jeong, Tessa L. Cutler, John L. Hopper, Andreas Busjahn, Kimberly J. Saudino, Fuling Ji, Feng Ning, Zengchang Pang, Richard J. Rose, Markku Koskenvuo, Kauko Heikkilä, Wendy Cozen, Amie E. Hwang, Thomas M. Mack, Sisira H. Siribaddana, Matthew Hotopf, Athula Sumathipala, Fruhling Rijsdijk, Joohon Sung, Jina Kim, Jooyeon Lee, Sooji Lee, Tracy L. Nelson, Keith E. Whitfield, Qihua Tan, Dongfeng Zhang, Clare H. Llewellyn, Abigail Fisher, S. Alexandra Burt, Kelly L. Klump, Ariel Knafo-Noam, David Mankuta, Lior Abramson, Sarah E. Medland, Nicholas G. Martin, Grant W. Montgomery, Patrik K. E. Magnusson, Nancy L. Pedersen, Anna K. Dahl Aslan, Robin P. Corley, Brooke M. Huibregtse, Sevgi Y. Öncel, Fazil Aliev, Robert F. Krueger, Matt McGue, Shandell Pahlen, Gonneke Willemsen, Meike Bartels, Catharina E. M. van Beijsterveldt, Judy L. Silberg, Lindon J. Eaves, Hermine H. Maes, Jennifer R. Harris, Ingunn Brandt, Thomas S. Nilsen, Finn Rasmussen, Per Tynelius, Laura A. Baker, Catherine Tuvblad, Juan R. Ordoñana, Juan F. Sánchez-Romera, Lucia Colodro-Conde, Margaret Gatz, David A. Butler, Paul Lichtenstein, Jack H. Goldberg, K. Paige Harden, Elliot M. Tucker-Drob, Glen E. Duncan, Dedra Buchwald, Adam D. Tarnoki, David L. Tarnoki, Carol E. Franz, William S. Kremen, Michael J. Lyons, José A. Maia, Duarte L. Freitas, Eric Turkheimer, Thorkild I. A. Sørensen, Dorret I. Boomsma, Jaakko Kaprio
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- Journal:
- Twin Research and Human Genetics / Volume 20 / Issue 5 / October 2017
- Published online by Cambridge University Press:
- 04 October 2017, pp. 395-405
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Whether monozygotic (MZ) and dizygotic (DZ) twins differ from each other in a variety of phenotypes is important for genetic twin modeling and for inferences made from twin studies in general. We analyzed whether there were differences in individual, maternal and paternal education between MZ and DZ twins in a large pooled dataset. Information was gathered on individual education for 218,362 adult twins from 27 twin cohorts (53% females; 39% MZ twins), and on maternal and paternal education for 147,315 and 143,056 twins respectively, from 28 twin cohorts (52% females; 38% MZ twins). Together, we had information on individual or parental education from 42 twin cohorts representing 19 countries. The original education classifications were transformed to education years and analyzed using linear regression models. Overall, MZ males had 0.26 (95% CI [0.21, 0.31]) years and MZ females 0.17 (95% CI [0.12, 0.21]) years longer education than DZ twins. The zygosity difference became smaller in more recent birth cohorts for both males and females. Parental education was somewhat longer for fathers of DZ twins in cohorts born in 1990–1999 (0.16 years, 95% CI [0.08, 0.25]) and 2000 or later (0.11 years, 95% CI [0.00, 0.22]), compared with fathers of MZ twins. The results show that the years of both individual and parental education are largely similar in MZ and DZ twins. We suggest that the socio-economic differences between MZ and DZ twins are so small that inferences based upon genetic modeling of twin data are not affected.
Soil Seed Bank Responses to Postfire Herbicide and Native Seeding Treatments Designed to Control Bromus tectorum in a Pinyon–Juniper Woodland at Zion National Park, USA
- Hondo Brisbin, Andrea Thode, Matt Brooks, Karen Weber
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- Invasive Plant Science and Management / Volume 6 / Issue 1 / March 2013
- Published online by Cambridge University Press:
- 20 January 2017, pp. 118-129
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The continued threat of an invasive, annual brome (Bromus) species in the western United States has created the need for integrated approaches to postfire restoration. Additionally, the high germination rate, high seed production, and seed bank carryover of annual bromes points to the need to assay soil seed banks as part of monitoring programs. We sampled the soil seed bank to help assess the effectiveness of treatments utilizing the herbicide Plateau® (imazapic) and a perennial native seed mix to control annual Bromus species and enhance perennial native plant establishment following a wildfire in Zion National Park, Utah. This study is one of few that have monitored the effects of imazapic and native seeding on a soil seed bank community and the only one that we know of that has done so in a pinyon–juniper woodland. The study made use of untreated, replicated controls, which is not common for seed bank studies. One year posttreatment, Bromus was significantly reduced in plots sprayed with herbicide. By the second year posttreatment, the effects of imazapic were less evident and convergence with the controls was evident. Emergence of seeded species was low for the duration of the study. Dry conditions and possible interactions with imazapic probably contributed to the lack of emergence of seeded native species. The perennial grass sand dropseed outperformed the other species included in the seed mix. We also examined how the treatments affected the soil seed bank community as a whole. We found evidence that the herbicide was reducing several native annual forbs and one nonnative annual forb. However, overall effects on the community were not significant. The results of our study were similar to what others have found in that imazapic is effective in providing a short-term reduction in Bromus density, although it can impact emergence of nontarget species.
Zygosity Differences in Height and Body Mass Index of Twins From Infancy to Old Age: A Study of the CODATwins Project
- Aline Jelenkovic, Yoshie Yokoyama, Reijo Sund, Chika Honda, Leonie H Bogl, Sari Aaltonen, Fuling Ji, Feng Ning, Zengchang Pang, Juan R. Ordoñana, Juan F. Sánchez-Romera, Lucia Colodro-Conde, S. Alexandra Burt, Kelly L. Klump, Sarah E. Medland, Grant W. Montgomery, Christian Kandler, Tom A. McAdams, Thalia C. Eley, Alice M. Gregory, Kimberly J. Saudino, Lise Dubois, Michel Boivin, Adam D. Tarnoki, David L. Tarnoki, Claire M. A. Haworth, Robert Plomin, Sevgi Y. Öncel, Fazil Aliev, Maria A. Stazi, Corrado Fagnani, Cristina D’Ippolito, Jeffrey M. Craig, Richard Saffery, Sisira H. Siribaddana, Matthew Hotopf, Athula Sumathipala, Fruhling Rijsdijk, Timothy Spector, Massimo Mangino, Genevieve Lachance, Margaret Gatz, David A. Butler, Gombojav Bayasgalan, Danshiitsoodol Narandalai, Duarte L Freitas, José Antonio Maia, K. Paige Harden, Elliot M. Tucker-Drob, Bia Kim, Youngsook Chong, Changhee Hong, Hyun Jung Shin, Kaare Christensen, Axel Skytthe, Kirsten O. Kyvik, Catherine A. Derom, Robert F. Vlietinck, Ruth J. F. Loos, Wendy Cozen, Amie E. Hwang, Thomas M. Mack, Mingguang He, Xiaohu Ding, Billy Chang, Judy L. Silberg, Lindon J. Eaves, Hermine H. Maes, Tessa L. Cutler, John L. Hopper, Kelly Aujard, Patrik K. E. Magnusson, Nancy L. Pedersen, Anna K. Dahl Aslan, Yun-Mi Song, Sarah Yang, Kayoung Lee, Laura A. Baker, Catherine Tuvblad, Morten Bjerregaard-Andersen, Henning Beck-Nielsen, Morten Sodemann, Kauko Heikkilä, Qihua Tan, Dongfeng Zhang, Gary E. Swan, Ruth Krasnow, Kerry L. Jang, Ariel Knafo-Noam, David Mankuta, Lior Abramson, Paul Lichtenstein, Robert F. Krueger, Matt McGue, Shandell Pahlen, Per Tynelius, Glen E. Duncan, Dedra Buchwald, Robin P. Corley, Brooke M. Huibregtse, Tracy L. Nelson, Keith E. Whitfield, Carol E. Franz, William S. Kremen, Michael J. Lyons, Syuichi Ooki, Ingunn Brandt, Thomas Sevenius Nilsen, Fujio Inui, Mikio Watanabe, Meike Bartels, Toos C. E. M. van Beijsterveldt, Jane Wardle, Clare H. Llewellyn, Abigail Fisher, Esther Rebato, Nicholas G. Martin, Yoshinori Iwatani, Kazuo Hayakawa, Joohon Sung, Jennifer R. Harris, Gonneke Willemsen, Andreas Busjahn, Jack H. Goldberg, Finn Rasmussen, Yoon-Mi Hur, Dorret I. Boomsma, Thorkild I. A. Sørensen, Jaakko Kaprio, Karri Silventoinen
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- Journal:
- Twin Research and Human Genetics / Volume 18 / Issue 5 / October 2015
- Published online by Cambridge University Press:
- 04 September 2015, pp. 557-570
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A trend toward greater body size in dizygotic (DZ) than in monozygotic (MZ) twins has been suggested by some but not all studies, and this difference may also vary by age. We analyzed zygosity differences in mean values and variances of height and body mass index (BMI) among male and female twins from infancy to old age. Data were derived from an international database of 54 twin cohorts participating in the COllaborative project of Development of Anthropometrical measures in Twins (CODATwins), and included 842,951 height and BMI measurements from twins aged 1 to 102 years. The results showed that DZ twins were consistently taller than MZ twins, with differences of up to 2.0 cm in childhood and adolescence and up to 0.9 cm in adulthood. Similarly, a greater mean BMI of up to 0.3 kg/m2 in childhood and adolescence and up to 0.2 kg/m2 in adulthood was observed in DZ twins, although the pattern was less consistent. DZ twins presented up to 1.7% greater height and 1.9% greater BMI than MZ twins; these percentage differences were largest in middle and late childhood and decreased with age in both sexes. The variance of height was similar in MZ and DZ twins at most ages. In contrast, the variance of BMI was significantly higher in DZ than in MZ twins, particularly in childhood. In conclusion, DZ twins were generally taller and had greater BMI than MZ twins, but the differences decreased with age in both sexes.
The CODATwins Project: The Cohort Description of Collaborative Project of Development of Anthropometrical Measures in Twins to Study Macro-Environmental Variation in Genetic and Environmental Effects on Anthropometric Traits
- Karri Silventoinen, Aline Jelenkovic, Reijo Sund, Chika Honda, Sari Aaltonen, Yoshie Yokoyama, Adam D. Tarnoki, David L. Tarnoki, Feng Ning, Fuling Ji, Zengchang Pang, Juan R. Ordoñana, Juan F. Sánchez-Romera, Lucia Colodro-Conde, S. Alexandra Burt, Kelly L. Klump, Sarah E. Medland, Grant W. Montgomery, Christian Kandler, Tom A. McAdams, Thalia C. Eley, Alice M. Gregory, Kimberly J. Saudino, Lise Dubois, Michel Boivin, Claire M. A. Haworth, Robert Plomin, Sevgi Y. Öncel, Fazil Aliev, Maria A. Stazi, Corrado Fagnani, Cristina D’Ippolito, Jeffrey M. Craig, Richard Saffery, Sisira H. Siribaddana, Matthew Hotopf, Athula Sumathipala, Timothy Spector, Massimo Mangino, Genevieve Lachance, Margaret Gatz, David A. Butler, Gombojav Bayasgalan, Danshiitsoodol Narandalai, Duarte L. Freitas, José Antonio Maia, K. Paige Harden, Elliot M. Tucker-Drob, Kaare Christensen, Axel Skytthe, Kirsten O. Kyvik, Changhee Hong, Youngsook Chong, Catherine A. Derom, Robert F. Vlietinck, Ruth J. F. Loos, Wendy Cozen, Amie E. Hwang, Thomas M. Mack, Mingguang He, Xiaohu Ding, Billy Chang, Judy L. Silberg, Lindon J. Eaves, Hermine H. Maes, Tessa L. Cutler, John L. Hopper, Kelly Aujard, Patrik K. E. Magnusson, Nancy L. Pedersen, Anna K. Dahl Aslan, Yun-Mi Song, Sarah Yang, Kayoung Lee, Laura A. Baker, Catherine Tuvblad, Morten Bjerregaard-Andersen, Henning Beck-Nielsen, Morten Sodemann, Kauko Heikkilä, Qihua Tan, Dongfeng Zhang, Gary E. Swan, Ruth Krasnow, Kerry L. Jang, Ariel Knafo-Noam, David Mankuta, Lior Abramson, Paul Lichtenstein, Robert F. Krueger, Matt McGue, Shandell Pahlen, Per Tynelius, Glen E. Duncan, Dedra Buchwald, Robin P. Corley, Brooke M. Huibregtse, Tracy L. Nelson, Keith E. Whitfield, Carol E. Franz, William S. Kremen, Michael J. Lyons, Syuichi Ooki, Ingunn Brandt, Thomas Sevenius Nilsen, Fujio Inui, Mikio Watanabe, Meike Bartels, Toos C. E. M. van Beijsterveldt, Jane Wardle, Clare H. Llewellyn, Abigail Fisher, Esther Rebato, Nicholas G. Martin, Yoshinori Iwatani, Kazuo Hayakawa, Finn Rasmussen, Joohon Sung, Jennifer R. Harris, Gonneke Willemsen, Andreas Busjahn, Jack H. Goldberg, Dorret I. Boomsma, Yoon-Mi Hur, Thorkild I. A. Sørensen, Jaakko Kaprio
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- Journal:
- Twin Research and Human Genetics / Volume 18 / Issue 4 / August 2015
- Published online by Cambridge University Press:
- 27 May 2015, pp. 348-360
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For over 100 years, the genetics of human anthropometric traits has attracted scientific interest. In particular, height and body mass index (BMI, calculated as kg/m2) have been under intensive genetic research. However, it is still largely unknown whether and how heritability estimates vary between human populations. Opportunities to address this question have increased recently because of the establishment of many new twin cohorts and the increasing accumulation of data in established twin cohorts. We started a new research project to analyze systematically (1) the variation of heritability estimates of height, BMI and their trajectories over the life course between birth cohorts, ethnicities and countries, and (2) to study the effects of birth-related factors, education and smoking on these anthropometric traits and whether these effects vary between twin cohorts. We identified 67 twin projects, including both monozygotic (MZ) and dizygotic (DZ) twins, using various sources. We asked for individual level data on height and weight including repeated measurements, birth related traits, background variables, education and smoking. By the end of 2014, 48 projects participated. Together, we have 893,458 height and weight measures (52% females) from 434,723 twin individuals, including 201,192 complete twin pairs (40% monozygotic, 40% same-sex dizygotic and 20% opposite-sex dizygotic) representing 22 countries. This project demonstrates that large-scale international twin studies are feasible and can promote the use of existing data for novel research purposes.
Contributors
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- By Mona Aboulghar, Mostafa Abuzeid, Valentine Akande, Carolyn J. Alexander, Gautam N. Allahbadia, Vicki Arguello, Nabil Aziz, Osama M. Azmy, Shawky Z. A. Badawy, Susan L. Baker, Tony Bazi, Nicole Brooks, Robin Brown, William W. Brown, Maria Cerrillo, Rebecca Chilvers, Angela Clough, Willie Cotten, Alan H. DeCherney, Aygul Demirol, Richard Palmer Dickey, Essam S. Dimitry, Maria Dimitry, Tiffany Driver, Alaa El-Ebrashy, Kareem El-Nahhas, Amr Etman, Aimee Eyvazzadeh, Juan A. Garcia-Velasco, Tarek A. Gelbaya, Seth Granberg, Timur Gurgan, Gurkan Levent, Suleyman Guven, Lars Hamberger, Andrew C. Harbin, Wayne J. G. Hellstrom, Micah J. Hill, James Hole, Yakoub Khalaf, John C. LaFleur, Deborah Levine, Iwan Lewis-Jones, Edward A. Lyons, Diana M. Marcus, Samuel F. Marcus, Mohamed F. M. Mitwally, Hany F. Moustafa, Manubai Nagamani, Luciano G. Nardo, Mary G. Nawar, Moshood Olatinwo, Lia Ornat, Sheri Owens, Kathy B. Porter, Jose M. Puente, Puscheck Elizabeth, Rizk Botros, Christine B. Rizk, Christopher B. Rizk, Hassan N. Sallam, Dimitrios Siassakos, Youssef Simaika, Stuart J. Singer, Brad Steffler, Annika Strandell, Sherri K. Taylor, Antoine Watrelot, Matts Wikland, Tony G. Zreik
- Edited by Botros R. M. B. Rizk, University of South Alabama
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- Book:
- Ultrasonography in Reproductive Medicine and Infertility
- Published online:
- 07 September 2011
- Print publication:
- 25 March 2010, pp ix-xii
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3 - Delineating Key Biodiversity Areas as targets for protecting areas
- from Part I - Conservation needs and priorities
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- By Thomas M. Brooks, Center for Applied Biodiversity Science Conservation International, Washington, Naamal De Silva, ICRAF – The World Agroforestry Centre, PO Box 35024 University of the Philippines, Los Baños, Laguna 4031, Philippines., Melizar V. Duya, Conservation International – Philippines 6 Maalalahanin St, Teacher's Village, Diliman, Quezon City, 1101 Philippines., Matt Foster, ICRAF – The World Agroforestry Centre University of the Philippines, David Knox, ICRAF – The World Agroforestry Centre, PO Box 35024 University of the Philippines, Los Baños, Laguna 4031, Philippines., Penny Langhammer, ICRAF – The World Agroforestry Centre, PO Box 35024 University of the Philippines, Los Baños, Laguna 4031, Philippines., Marthy R. William, Conservation International – Indonesia Jl Pejaten Barat 16 A, Kemang, Jakarta – 12550, Indonesia., Blas Tabaranza, Jr., Haribon Foundation for the Conservation of Natural Resources, 4th Floor Fil-Garcia Tower, 140 Kalayaan Ave at Mayaman St Diliman, Quezon City, 1101 Philippines.
- Edited by Navjot S. Sodhi, National University of Singapore, Greg Acciaioli, National University of Singapore, Maribeth Erb, National University of Singapore, Alan Khee-Jin Tan, National University of Singapore
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- Book:
- Biodiversity and Human Livelihoods in Protected Areas
- Published online:
- 12 November 2009
- Print publication:
- 22 November 2007, pp 20-35
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Summary
Introduction
Biodiversity faces a crisis, with extinction rates approximately three orders of magnitude higher than those typical of the Earth's history (Pimm et al. 1995). This crisis has numerous negative consequences for humanity, including to economies, health, environmental services, and moral and spiritual well-being (Wilson 2002). The biodiversity crisis is particularly serious in Southeast Asia (Sodhi et al. 2004; Sodhi & Brook 2006), where wholesale extinctions are already in the process of unfolding (Brook et al. 2003). Among a large number of causes of these extinctions, the destruction of natural habitats is the most pervasive, affecting ~90% of all threatened species (Baillie et al. 2004). Given this, it is clear that the primary tactic necessary to stem the crisis is to safeguard sites of global biodiversity significance. This has received intergovernmental mandate, with, for example, the 188 parties to the Convention on Biological Diversity agreeing on a Programme of Work on Protected Areas (http://www.biodiv.org/programmes/cross-cutting/protected) to support the establishment and maintenance ‘of comprehensive, effectively managed, and ecologically representative national and regional systems of protected areas’ (Decision VII/28). However, this raises the question of how these sites can best be identified and delineated.
This chapter addresses this question. We begin by explaining the variety of factors that require consideration in the identification of those areas requiring site safeguard. Next, we show how the approach of identifying and delineating Key Biodiversity Areas (KBAs) emerges from these considerations. Finally, we discuss the issue of how KBAs can best be delineated.