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href="/archive/issues/1995/">1995</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/1996/">1996</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/1997/">1997</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/1998/">1998</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/1999/">1999</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/2000/">2000</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/2001/">2001</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/2002/">2002</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/2003/">2003</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/2004/">2004</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/2005/">2005</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/2006/">2006</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/2007/">2007</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/2008/">2008</a><a class="date-selector exact selected" style="cursor:pointer;border:1px solid #09396922;color:#093969;background-color:#3576b322;border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:700;text-decoration:none" href="/archive/issues/2009/">2009</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/2010/">2010</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/2011/">2011</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/2012/">2012</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/2013/">2013</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/2014/">2014</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/2015/">2015</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/2016/">2016</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/2017/">2017</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/2018/">2018</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/2019/">2019</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/2020/">2020</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/2021/">2021</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/2022/">2022</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/2023/">2023</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/2024/">2024</a></div></div></div><div class="issue__list-8JHD2"><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/sa/2009/12-01/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/CAC97CE8-44E0-41B1-8BB5E70F5FB9E6A1_source.jpg?w=600" alt="Scientific American Magazine Vol 301 Issue 6" srcSet="https://static.scientificamerican.com/sciam/cache/file/CAC97CE8-44E0-41B1-8BB5E70F5FB9E6A1_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/CAC97CE8-44E0-41B1-8BB5E70F5FB9E6A1_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Scientific American</h3><div class="issue__date-ozuG1"><time dateTime="2009-12-01">December 2009</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/sa/2009/11-01/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/915E5926-713B-4C16-B6662D094CCCCA93_source.jpg?w=600" alt="Scientific American Magazine Vol 301 Issue 5" srcSet="https://static.scientificamerican.com/sciam/cache/file/915E5926-713B-4C16-B6662D094CCCCA93_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/915E5926-713B-4C16-B6662D094CCCCA93_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Scientific American</h3><div class="issue__date-ozuG1"><time dateTime="2009-11-01">November 2009</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/mind/2009/11-01/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/94AD38AD-1DC2-44CA-BA6F5C2E7CCF60D6_source.jpg?w=600" alt="SA Mind Vol 20 Issue 6" srcSet="https://static.scientificamerican.com/sciam/cache/file/94AD38AD-1DC2-44CA-BA6F5C2E7CCF60D6_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/94AD38AD-1DC2-44CA-BA6F5C2E7CCF60D6_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Mind</h3><div class="issue__date-ozuG1"><time dateTime="2009-11-01">November 2009</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/sa/2009/10-01/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/BDE4F595-7770-443B-8543812B283FCE79_source.jpg?w=600" alt="Scientific American Magazine Vol 301 Issue 4" srcSet="https://static.scientificamerican.com/sciam/cache/file/BDE4F595-7770-443B-8543812B283FCE79_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/BDE4F595-7770-443B-8543812B283FCE79_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Scientific American</h3><div class="issue__date-ozuG1"><time dateTime="2009-10-01">October 2009</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/sa/2009/09-01/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/45BA88B1-452C-4EB9-A9E709361A74E812_source.jpg?w=600" alt="Scientific American Magazine Vol 301 Issue 3" srcSet="https://static.scientificamerican.com/sciam/cache/file/45BA88B1-452C-4EB9-A9E709361A74E812_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/45BA88B1-452C-4EB9-A9E709361A74E812_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Scientific American</h3><div class="issue__date-ozuG1"><time dateTime="2009-09-01">September 2009</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/mind/2009/09-01/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/1ED62F43-5E3D-43D9-BBAD5D13B9B283EF_source.jpg?w=600" alt="SA Mind Vol 20 Issue 5" srcSet="https://static.scientificamerican.com/sciam/cache/file/1ED62F43-5E3D-43D9-BBAD5D13B9B283EF_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/1ED62F43-5E3D-43D9-BBAD5D13B9B283EF_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Mind</h3><div class="issue__date-ozuG1"><time dateTime="2009-09-01">September 2009</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/sa/2009/08-01/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/E6F80DB8-BEAF-4B50-BECBCE3A2D134DD6_source.jpg?w=600" alt="Scientific American Magazine Vol 301 Issue 2" srcSet="https://static.scientificamerican.com/sciam/cache/file/E6F80DB8-BEAF-4B50-BECBCE3A2D134DD6_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/E6F80DB8-BEAF-4B50-BECBCE3A2D134DD6_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Scientific American</h3><div class="issue__date-ozuG1"><time dateTime="2009-08-01">August 2009</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/sa/2009/07-01/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/93826DE3-0557-4166-9560F7F69B9C0C8F_source.jpg?w=600" alt="Scientific American Magazine Vol 301 Issue 1" srcSet="https://static.scientificamerican.com/sciam/cache/file/93826DE3-0557-4166-9560F7F69B9C0C8F_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/93826DE3-0557-4166-9560F7F69B9C0C8F_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Scientific American</h3><div class="issue__date-ozuG1"><time dateTime="2009-07-01">July 2009</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/mind/2009/07-01/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/EA145E9F-7266-4E96-8A133513A6610A0E_source.jpg?w=600" alt="SA Mind Vol 20 Issue 4" srcSet="https://static.scientificamerican.com/sciam/cache/file/EA145E9F-7266-4E96-8A133513A6610A0E_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/EA145E9F-7266-4E96-8A133513A6610A0E_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Mind</h3><div class="issue__date-ozuG1"><time dateTime="2009-07-01">July 2009</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/special-editions/2009/population-sustainability/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/5D25EA58-8FA6-43D5-BF89DAD668F5411B_source.jpg?w=600" alt="SA Special Editions Vol 19 Issue 2s" srcSet="https://static.scientificamerican.com/sciam/cache/file/5D25EA58-8FA6-43D5-BF89DAD668F5411B_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/5D25EA58-8FA6-43D5-BF89DAD668F5411B_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Special Edition</h3><div class="issue__date-ozuG1"><time dateTime="2009-06-01">June 2009</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/sa/2009/06-01/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/4FE66ACA-420C-4BD7-A70398D25FA068E9_source.jpg?w=600" alt="Scientific American Magazine Vol 300 Issue 6" srcSet="https://static.scientificamerican.com/sciam/cache/file/4FE66ACA-420C-4BD7-A70398D25FA068E9_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/4FE66ACA-420C-4BD7-A70398D25FA068E9_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Scientific American</h3><div class="issue__date-ozuG1"><time dateTime="2009-06-01">June 2009</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/sa/2009/05-01/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/454F4119-3A28-4B87-9C21705D6791C23F_source.jpg?w=600" alt="Scientific American Magazine Vol 300 Issue 5" srcSet="https://static.scientificamerican.com/sciam/cache/file/454F4119-3A28-4B87-9C21705D6791C23F_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/454F4119-3A28-4B87-9C21705D6791C23F_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Scientific American</h3><div class="issue__date-ozuG1"><time dateTime="2009-05-01">May 2009</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/sa/2009/04-01/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/29C0A422-C6BF-40D8-A72EEC23926D3AFC_source.jpg?w=600" alt="Scientific American Magazine Vol 300 Issue 4" srcSet="https://static.scientificamerican.com/sciam/cache/file/29C0A422-C6BF-40D8-A72EEC23926D3AFC_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/29C0A422-C6BF-40D8-A72EEC23926D3AFC_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Scientific American</h3><div class="issue__date-ozuG1"><time dateTime="2009-04-01">April 2009</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/mind/2009/04-01/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/8ED875DC-1DA8-4F2B-8625975BCC3897B1_source.jpg?w=600" alt="SA Mind Vol 20 Issue 2" srcSet="https://static.scientificamerican.com/sciam/cache/file/8ED875DC-1DA8-4F2B-8625975BCC3897B1_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/8ED875DC-1DA8-4F2B-8625975BCC3897B1_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Mind</h3><div class="issue__date-ozuG1"><time dateTime="2009-04-01">April 2009</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/sa/2009/03-01/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/94EE9B26-8B8A-4A1C-9BBFDF71850047C4_source.jpg?w=600" alt="Scientific American Magazine Vol 300 Issue 3" srcSet="https://static.scientificamerican.com/sciam/cache/file/94EE9B26-8B8A-4A1C-9BBFDF71850047C4_source.jpg?w=300 300w, 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