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Distribution, abundance, and on-land threats to Cabo Verde seabirds
- GILSON SEMEDO, VITOR H. PAIVA, TERESA MILITÃO, ISABEL RODRIGUES, HERCULANO A. DINIS, JORGE PEREIRA, DIANA MATOS, FILIPE R. CEIA, NATHALIE M. ALMEIDA, PEDRO GERALDES, SARAH SALDANHA, NADITO BARBOSA, MARCOS HERNÁNDEZ-MONTERO, CAROLINO FERNANDES, JACOB GONZÁLEZ-SÓLIS, JAIME A. RAMOS
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- Journal:
- Bird Conservation International / Volume 31 / Issue 1 / March 2021
- Published online by Cambridge University Press:
- 28 August 2020, pp. 53-76
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Pelagic seabird populations have declined strongly worldwide. In the North Atlantic there was a huge reduction in seabird populations following the European colonization of the Azores, Madeira and Canary archipelagos but information on seabird status and distribution for the subtropical region of Cabo Verde is scarce, unavailable or dispersed in grey literature. We compiled and compared the historical and current distribution of all seabird species breeding in the Cabo Verde archipelago, updated their relative abundance, investigated their inland habitat preferences, and reviewed their threats. Currently, the breeding seabird community in Cabo Verde is composed of Bulwer’s Petrel Bulweria bulwerii, White-faced Storm-petrel Pelagodroma marina aedesorum, Cape Verde Shearwater Calonectris edwardsii, Cape Verde Storm-petrel Hydrobates jabejabe, Cape Verde Petrel Pterodroma feae, Boyd's Shearwater Puffinus lherminieri boydi, Brown Booby Sula leucogaster, and Red-billed Tropicbird Phaethon aethereus. One breeding species is currently extinct, the Magnificent Frigatebird Fregata magnificens. The relative abundance of Cape Verde Shearwater, Boyd’s Shearwater, Cape Verde Petrel, and Cape Verde Storm-petrel was determined from counts of their nocturnal calls in Santo Antão, São Vicente, Santa Luzia, Branco, Raso and São Nicolau. Cape Verde Petrel occurred only on mountainous islands (Santo Antão, São Nicolau, Santiago, and Fogo) from mid-to high elevations. Larger species such as the Cape Verde Shearwater and Boyd’s Shearwater exhibited a wider distribution in the archipelago, occurring close to the coastline but at lower densities on populated islands. Small procellariforms such as the Cape Verde Storm-petrel occurred at high densities only on rat-free islets and in steep areas of main islands where introduced cats and rats are unlikely to occur. The main threats to seabird populations in Cabo Verde range from predation by introduced predators, habitat alteration or destruction, and some residual human persecution.
5 - Evolution of color vision and its reflections in contemporary mammals
- from Part II - Foundations: basics of color science
- Edited by Andrew J. Elliot, University of Rochester, New York, Mark D. Fairchild, Rochester Institute of Technology, New York, Anna Franklin, University of Sussex
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- Book:
- Handbook of Color Psychology
- Published online:
- 05 April 2016
- Print publication:
- 17 December 2015, pp 110-130
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Contributors
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- By Mitchell Aboulafia, Frederick Adams, Marilyn McCord Adams, Robert M. Adams, Laird Addis, James W. Allard, David Allison, William P. Alston, Karl Ameriks, C. Anthony Anderson, David Leech Anderson, Lanier Anderson, Roger Ariew, David Armstrong, Denis G. Arnold, E. J. Ashworth, Margaret Atherton, Robin Attfield, Bruce Aune, Edward Wilson Averill, Jody Azzouni, Kent Bach, Andrew Bailey, Lynne Rudder Baker, Thomas R. Baldwin, Jon Barwise, George Bealer, William Bechtel, Lawrence C. Becker, Mark A. Bedau, Ernst Behler, José A. Benardete, Ermanno Bencivenga, Jan Berg, Michael Bergmann, Robert L. Bernasconi, Sven Bernecker, Bernard Berofsky, Rod Bertolet, Charles J. Beyer, Christian Beyer, Joseph Bien, Joseph Bien, Peg Birmingham, Ivan Boh, James Bohman, Daniel Bonevac, Laurence BonJour, William J. Bouwsma, Raymond D. Bradley, Myles Brand, Richard B. Brandt, Michael E. Bratman, Stephen E. Braude, Daniel Breazeale, Angela Breitenbach, Jason Bridges, David O. Brink, Gordon G. Brittan, Justin Broackes, Dan W. Brock, Aaron Bronfman, Jeffrey E. Brower, Bartosz Brozek, Anthony Brueckner, Jeffrey Bub, Lara Buchak, Otavio Bueno, Ann E. Bumpus, Robert W. Burch, John Burgess, Arthur W. Burks, Panayot Butchvarov, Robert E. Butts, Marina Bykova, Patrick Byrne, David Carr, Noël Carroll, Edward S. Casey, Victor Caston, Victor Caston, Albert Casullo, Robert L. Causey, Alan K. L. Chan, Ruth Chang, Deen K. Chatterjee, Andrew Chignell, Roderick M. Chisholm, Kelly J. Clark, E. J. Coffman, Robin Collins, Brian P. Copenhaver, John Corcoran, John Cottingham, Roger Crisp, Frederick J. Crosson, Antonio S. Cua, Phillip D. Cummins, Martin Curd, Adam Cureton, Andrew Cutrofello, Stephen Darwall, Paul Sheldon Davies, Wayne A. Davis, Timothy Joseph Day, Claudio de Almeida, Mario De Caro, Mario De Caro, John Deigh, C. F. Delaney, Daniel C. Dennett, Michael R. DePaul, Michael Detlefsen, Daniel Trent Devereux, Philip E. Devine, John M. Dillon, Martin C. Dillon, Robert DiSalle, Mary Domski, Alan Donagan, Paul Draper, Fred Dretske, Mircea Dumitru, Wilhelm Dupré, Gerald Dworkin, John Earman, Ellery Eells, Catherine Z. Elgin, Berent Enç, Ronald P. Endicott, Edward Erwin, John Etchemendy, C. Stephen Evans, Susan L. Feagin, Solomon Feferman, Richard Feldman, Arthur Fine, Maurice A. Finocchiaro, William FitzPatrick, Richard E. Flathman, Gvozden Flego, Richard Foley, Graeme Forbes, Rainer Forst, Malcolm R. Forster, Daniel Fouke, Patrick Francken, Samuel Freeman, Elizabeth Fricker, Miranda Fricker, Michael Friedman, Michael Fuerstein, Richard A. Fumerton, Alan Gabbey, Pieranna Garavaso, Daniel Garber, Jorge L. A. Garcia, Robert K. Garcia, Don Garrett, Philip Gasper, Gerald Gaus, Berys Gaut, Bernard Gert, Roger F. Gibson, Cody Gilmore, Carl Ginet, Alan H. Goldman, Alvin I. Goldman, Alfonso Gömez-Lobo, Lenn E. Goodman, Robert M. Gordon, Stefan Gosepath, Jorge J. E. Gracia, Daniel W. Graham, George A. Graham, Peter J. Graham, Richard E. Grandy, I. Grattan-Guinness, John Greco, Philip T. Grier, Nicholas Griffin, Nicholas Griffin, David A. Griffiths, Paul J. Griffiths, Stephen R. Grimm, Charles L. Griswold, Charles B. Guignon, Pete A. Y. Gunter, Dimitri Gutas, Gary Gutting, Paul Guyer, Kwame Gyekye, Oscar A. Haac, Raul Hakli, Raul Hakli, Michael Hallett, Edward C. Halper, Jean Hampton, R. James Hankinson, K. R. Hanley, Russell Hardin, Robert M. Harnish, William Harper, David Harrah, Kevin Hart, Ali Hasan, William Hasker, John Haugeland, Roger Hausheer, William Heald, Peter Heath, Richard Heck, John F. Heil, Vincent F. Hendricks, Stephen Hetherington, Francis Heylighen, Kathleen Marie Higgins, Risto Hilpinen, Harold T. Hodes, Joshua Hoffman, Alan Holland, Robert L. Holmes, Richard Holton, Brad W. Hooker, Terence E. Horgan, Tamara Horowitz, Paul Horwich, Vittorio Hösle, Paul Hoβfeld, Daniel Howard-Snyder, Frances Howard-Snyder, Anne Hudson, Deal W. Hudson, Carl A. Huffman, David L. Hull, Patricia Huntington, Thomas Hurka, Paul Hurley, Rosalind Hursthouse, Guillermo Hurtado, Ronald E. Hustwit, Sarah Hutton, Jonathan Jenkins Ichikawa, Harry A. Ide, David Ingram, Philip J. Ivanhoe, Alfred L. Ivry, Frank Jackson, Dale Jacquette, Joseph Jedwab, Richard Jeffrey, David Alan Johnson, Edward Johnson, Mark D. Jordan, Richard Joyce, Hwa Yol Jung, Robert Hillary Kane, Tomis Kapitan, Jacquelyn Ann K. Kegley, James A. Keller, Ralph Kennedy, Sergei Khoruzhii, Jaegwon Kim, Yersu Kim, Nathan L. King, Patricia Kitcher, Peter D. Klein, E. D. Klemke, Virginia Klenk, George L. Kline, Christian Klotz, Simo Knuuttila, Joseph J. Kockelmans, Konstantin Kolenda, Sebastian Tomasz Kołodziejczyk, Isaac Kramnick, Richard Kraut, Fred Kroon, Manfred Kuehn, Steven T. Kuhn, Henry E. Kyburg, John Lachs, Jennifer Lackey, Stephen E. Lahey, Andrea Lavazza, Thomas H. Leahey, Joo Heung Lee, Keith Lehrer, Dorothy Leland, Noah M. Lemos, Ernest LePore, Sarah-Jane Leslie, Isaac Levi, Andrew Levine, Alan E. Lewis, Daniel E. Little, Shu-hsien Liu, Shu-hsien Liu, Alan K. L. Chan, Brian Loar, Lawrence B. Lombard, John Longeway, Dominic McIver Lopes, Michael J. Loux, E. J. Lowe, Steven Luper, Eugene C. Luschei, William G. Lycan, David Lyons, David Macarthur, Danielle Macbeth, Scott MacDonald, Jacob L. Mackey, Louis H. Mackey, Penelope Mackie, Edward H. Madden, Penelope Maddy, G. B. Madison, Bernd Magnus, Pekka Mäkelä, Rudolf A. Makkreel, David Manley, William E. Mann (W.E.M.), Vladimir Marchenkov, Peter Markie, Jean-Pierre Marquis, Ausonio Marras, Mike W. Martin, A. P. Martinich, William L. McBride, David McCabe, Storrs McCall, Hugh J. McCann, Robert N. McCauley, John J. McDermott, Sarah McGrath, Ralph McInerny, Daniel J. McKaughan, Thomas McKay, Michael McKinsey, Brian P. McLaughlin, Ernan McMullin, Anthonie Meijers, Jack W. Meiland, William Jason Melanson, Alfred R. Mele, Joseph R. Mendola, Christopher Menzel, Michael J. Meyer, Christian B. Miller, David W. Miller, Peter Millican, Robert N. Minor, Phillip Mitsis, James A. Montmarquet, Michael S. Moore, Tim Moore, Benjamin Morison, Donald R. Morrison, Stephen J. Morse, Paul K. Moser, Alexander P. D. Mourelatos, Ian Mueller, James Bernard Murphy, Mark C. Murphy, Steven Nadler, Jan Narveson, Alan Nelson, Jerome Neu, Samuel Newlands, Kai Nielsen, Ilkka Niiniluoto, Carlos G. Noreña, Calvin G. Normore, David Fate Norton, Nikolaj Nottelmann, Donald Nute, David S. Oderberg, Steve Odin, Michael O’Rourke, Willard G. Oxtoby, Heinz Paetzold, George S. Pappas, Anthony J. Parel, Lydia Patton, R. P. Peerenboom, Francis Jeffry Pelletier, Adriaan T. Peperzak, Derk Pereboom, Jaroslav Peregrin, Glen Pettigrove, Philip Pettit, Edmund L. Pincoffs, Andrew Pinsent, Robert B. Pippin, Alvin Plantinga, Louis P. Pojman, Richard H. Popkin, John F. Post, Carl J. Posy, William J. Prior, Richard Purtill, Michael Quante, Philip L. Quinn, Philip L. Quinn, Elizabeth S. Radcliffe, Diana Raffman, Gerard Raulet, Stephen L. Read, Andrews Reath, Andrew Reisner, Nicholas Rescher, Henry S. Richardson, Robert C. Richardson, Thomas Ricketts, Wayne D. Riggs, Mark Roberts, Robert C. Roberts, Luke Robinson, Alexander Rosenberg, Gary Rosenkranz, Bernice Glatzer Rosenthal, Adina L. Roskies, William L. Rowe, T. M. Rudavsky, Michael Ruse, Bruce Russell, Lilly-Marlene Russow, Dan Ryder, R. M. Sainsbury, Joseph Salerno, Nathan Salmon, Wesley C. Salmon, Constantine Sandis, David H. Sanford, Marco Santambrogio, David Sapire, Ruth A. Saunders, Geoffrey Sayre-McCord, Charles Sayward, James P. Scanlan, Richard Schacht, Tamar Schapiro, Frederick F. Schmitt, Jerome B. Schneewind, Calvin O. Schrag, Alan D. Schrift, George F. Schumm, Jean-Loup Seban, David N. Sedley, Kenneth Seeskin, Krister Segerberg, Charlene Haddock Seigfried, Dennis M. Senchuk, James F. Sennett, William Lad Sessions, Stewart Shapiro, Tommie Shelby, Donald W. Sherburne, Christopher Shields, Roger A. Shiner, Sydney Shoemaker, Robert K. Shope, Kwong-loi Shun, Wilfried Sieg, A. John Simmons, Robert L. Simon, Marcus G. Singer, Georgette Sinkler, Walter Sinnott-Armstrong, Matti T. Sintonen, Lawrence Sklar, Brian Skyrms, Robert C. Sleigh, Michael Anthony Slote, Hans Sluga, Barry Smith, Michael Smith, Robin Smith, Robert Sokolowski, Robert C. Solomon, Marta Soniewicka, Philip Soper, Ernest Sosa, Nicholas Southwood, Paul Vincent Spade, T. L. S. Sprigge, Eric O. Springsted, George J. Stack, Rebecca Stangl, Jason Stanley, Florian Steinberger, Sören Stenlund, Christopher Stephens, James P. Sterba, Josef Stern, Matthias Steup, M. A. Stewart, Leopold Stubenberg, Edith Dudley Sulla, Frederick Suppe, Jere Paul Surber, David George Sussman, Sigrún Svavarsdóttir, Zeno G. Swijtink, Richard Swinburne, Charles C. Taliaferro, Robert B. Talisse, John Tasioulas, Paul Teller, Larry S. Temkin, Mark Textor, H. S. Thayer, Peter Thielke, Alan Thomas, Amie L. Thomasson, Katherine Thomson-Jones, Joshua C. Thurow, Vzalerie Tiberius, Terrence N. Tice, Paul Tidman, Mark C. Timmons, William Tolhurst, James E. Tomberlin, Rosemarie Tong, Lawrence Torcello, Kelly Trogdon, J. D. Trout, Robert E. Tully, Raimo Tuomela, John Turri, Martin M. Tweedale, Thomas Uebel, Jennifer Uleman, James Van Cleve, Harry van der Linden, Peter van Inwagen, Bryan W. Van Norden, René van Woudenberg, Donald Phillip Verene, Samantha Vice, Thomas Vinci, Donald Wayne Viney, Barbara Von Eckardt, Peter B. M. Vranas, Steven J. Wagner, William J. Wainwright, Paul E. Walker, Robert E. Wall, Craig Walton, Douglas Walton, Eric Watkins, Richard A. Watson, Michael V. Wedin, Rudolph H. Weingartner, Paul Weirich, Paul J. Weithman, Carl Wellman, Howard Wettstein, Samuel C. Wheeler, Stephen A. White, Jennifer Whiting, Edward R. Wierenga, Michael Williams, Fred Wilson, W. Kent Wilson, Kenneth P. Winkler, John F. Wippel, Jan Woleński, Allan B. Wolter, Nicholas P. Wolterstorff, Rega Wood, W. Jay Wood, Paul Woodruff, Alison Wylie, Gideon Yaffe, Takashi Yagisawa, Yutaka Yamamoto, Keith E. Yandell, Xiaomei Yang, Dean Zimmerman, Günter Zoller, Catherine Zuckert, Michael Zuckert, Jack A. Zupko (J.A.Z.)
- Edited by Robert Audi, University of Notre Dame, Indiana
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- Book:
- The Cambridge Dictionary of Philosophy
- Published online:
- 05 August 2015
- Print publication:
- 27 April 2015, pp ix-xxx
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Losses of functional opsin genes, short-wavelength cone photopigments, and color vision—A significant trend in the evolution of mammalian vision
- GERALD H. JACOBS
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- Journal:
- Visual Neuroscience / Volume 30 / Issue 1-2 / March 2013
- Published online by Cambridge University Press:
- 03 January 2013, pp. 39-53
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All mammalian cone photopigments are derived from the operation of representatives from two opsin gene families (SWS1 and LWS in marsupial and eutherian mammals; SWS2 and LWS in monotremes), a process that produces cone pigments with respective peak sensitivities in the short and middle-to-long wavelengths. With the exception of a number of primate taxa, the modal pattern for mammals is to have two types of cone photopigment, one drawn from each of the gene families. In recent years, it has been discovered that the SWS1 opsin genes of a widely divergent collection of eutherian mammals have accumulated mutational changes that render them nonfunctional. This alteration reduces the retinal complements of these species to a single cone type, thus rendering ordinary color vision impossible. At present, several dozen species from five mammalian orders have been identified as falling into this category, but the total number of mammalian species that have lost short-wavelength cones in this way is certain to be much larger, perhaps reaching as high as 10% of all species. A number of circumstances that might be used to explain this widespread cone loss can be identified. Among these, the single consistent fact is that the species so affected are nocturnal or, if they are not technically nocturnal, they at least feature retinal organizations that are typically associated with that lifestyle. At the same time, however, there are many nocturnal mammals that retain functional short-wavelength cones. Nocturnality thus appears to set the stage for loss of functional SWS1 opsin genes in mammals, but it cannot be the sole circumstance.
Data and interpretation in comparative color vision
- Gerald H. Jacobs
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- Journal:
- Behavioral and Brain Sciences / Volume 15 / Issue 1 / March 1992
- Published online by Cambridge University Press:
- 19 May 2011, pp. 40-41
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- By Rose Teteki Abbey, K. C. Abraham, David Tuesday Adamo, LeRoy H. Aden, Efrain Agosto, Victor Aguilan, Gillian T. W. Ahlgren, Charanjit Kaur AjitSingh, Dorothy B E A Akoto, Giuseppe Alberigo, Daniel E. Albrecht, Ruth Albrecht, Daniel O. Aleshire, Urs Altermatt, Anand Amaladass, Michael Amaladoss, James N. Amanze, Lesley G. Anderson, Thomas C. Anderson, Victor Anderson, Hope S. Antone, María Pilar Aquino, Paula Arai, Victorio Araya Guillén, S. Wesley Ariarajah, Ellen T. Armour, Brett Gregory Armstrong, Atsuhiro Asano, Naim Stifan Ateek, Mahmoud Ayoub, John Alembillah Azumah, Mercedes L. García Bachmann, Irena Backus, J. Wayne Baker, Mieke Bal, Lewis V. Baldwin, William Barbieri, António Barbosa da Silva, David Basinger, Bolaji Olukemi Bateye, Oswald Bayer, Daniel H. Bays, Rosalie Beck, Nancy Elizabeth Bedford, Guy-Thomas Bedouelle, Chorbishop Seely Beggiani, Wolfgang Behringer, Christopher M. Bellitto, Byard Bennett, Harold V. Bennett, Teresa Berger, Miguel A. Bernad, Henley Bernard, Alan E. Bernstein, Jon L. Berquist, Johannes Beutler, Ana María Bidegain, Matthew P. Binkewicz, Jennifer Bird, Joseph Blenkinsopp, Dmytro Bondarenko, Paulo Bonfatti, Riet en Pim Bons-Storm, Jessica A. Boon, Marcus J. Borg, Mark Bosco, Peter C. Bouteneff, François Bovon, William D. Bowman, Paul S. Boyer, David Brakke, Richard E. Brantley, Marcus Braybrooke, Ian Breward, Ênio José da Costa Brito, Jewel Spears Brooker, Johannes Brosseder, Nicholas Canfield Read Brown, Robert F. Brown, Pamela K. Brubaker, Walter Brueggemann, Bishop Colin O. Buchanan, Stanley M. Burgess, Amy Nelson Burnett, J. Patout Burns, David B. Burrell, David Buttrick, James P. Byrd, Lavinia Byrne, Gerado Caetano, Marcos Caldas, Alkiviadis Calivas, William J. Callahan, Salvatore Calomino, Euan K. Cameron, William S. Campbell, Marcelo Ayres Camurça, Daniel F. Caner, Paul E. Capetz, Carlos F. Cardoza-Orlandi, Patrick W. Carey, Barbara Carvill, Hal Cauthron, Subhadra Mitra Channa, Mark D. Chapman, James H. Charlesworth, Kenneth R. Chase, Chen Zemin, Luciano Chianeque, Philip Chia Phin Yin, Francisca H. Chimhanda, Daniel Chiquete, John T. Chirban, Soobin Choi, Robert Choquette, Mita Choudhury, Gerald Christianson, John Chryssavgis, Sejong Chun, Esther Chung-Kim, Charles M. A. Clark, Elizabeth A. Clark, Sathianathan Clarke, Fred Cloud, John B. Cobb, W. Owen Cole, John A Coleman, John J. Collins, Sylvia Collins-Mayo, Paul K. Conkin, Beth A. Conklin, Sean Connolly, Demetrios J. Constantelos, Michael A. Conway, Paula M. Cooey, Austin Cooper, Michael L. Cooper-White, Pamela Cooper-White, L. William Countryman, Sérgio Coutinho, Pamela Couture, Shannon Craigo-Snell, James L. Crenshaw, David Crowner, Humberto Horacio Cucchetti, Lawrence S. Cunningham, Elizabeth Mason Currier, Emmanuel Cutrone, Mary L. Daniel, David D. Daniels, Robert Darden, Rolf Darge, Isaiah Dau, Jeffry C. Davis, Jane Dawson, Valentin Dedji, John W. de Gruchy, Paul DeHart, Wendy J. Deichmann Edwards, Miguel A. De La Torre, George E. Demacopoulos, Thomas de Mayo, Leah DeVun, Beatriz de Vasconcellos Dias, Dennis C. Dickerson, John M. Dillon, Luis Miguel Donatello, Igor Dorfmann-Lazarev, Susanna Drake, Jonathan A. Draper, N. Dreher Martin, Otto Dreydoppel, Angelyn Dries, A. J. Droge, Francis X. D'Sa, Marilyn Dunn, Nicole Wilkinson Duran, Rifaat Ebied, Mark J. Edwards, William H. Edwards, Leonard H. Ehrlich, Nancy L. Eiesland, Martin Elbel, J. Harold Ellens, Stephen Ellingson, Marvin M. Ellison, Robert Ellsberg, Jean Bethke Elshtain, Eldon Jay Epp, Peter C. Erb, Tassilo Erhardt, Maria Erling, Noel Leo Erskine, Gillian R. Evans, Virginia Fabella, Michael A. Fahey, Edward Farley, Margaret A. Farley, Wendy Farley, Robert Fastiggi, Seena Fazel, Duncan S. Ferguson, Helwar Figueroa, Paul Corby Finney, Kyriaki Karidoyanes FitzGerald, Thomas E. FitzGerald, John R. Fitzmier, Marie Therese Flanagan, Sabina Flanagan, Claude Flipo, Ronald B. Flowers, Carole Fontaine, David Ford, Mary Ford, Stephanie A. Ford, Jim Forest, William Franke, Robert M. Franklin, Ruth Franzén, Edward H. Friedman, Samuel Frouisou, Lorelei F. Fuchs, Jojo M. Fung, Inger Furseth, Richard R. Gaillardetz, Brandon Gallaher, China Galland, Mark Galli, Ismael García, Tharscisse Gatwa, Jean-Marie Gaudeul, Luis María Gavilanes del Castillo, Pavel L. Gavrilyuk, Volney P. Gay, Metropolitan Athanasios Geevargis, Kondothra M. George, Mary Gerhart, Simon Gikandi, Maurice Gilbert, Michael J. Gillgannon, Verónica Giménez Beliveau, Terryl Givens, Beth Glazier-McDonald, Philip Gleason, Menghun Goh, Brian Golding, Bishop Hilario M. Gomez, Michelle A. Gonzalez, Donald K. Gorrell, Roy Gottfried, Tamara Grdzelidze, Joel B. Green, Niels Henrik Gregersen, Cristina Grenholm, Herbert Griffiths, Eric W. Gritsch, Erich S. Gruen, Christoffer H. Grundmann, Paul H. Gundani, Jon P. Gunnemann, Petre Guran, Vidar L. Haanes, Jeremiah M. Hackett, Getatchew Haile, Douglas John Hall, Nicholas Hammond, Daphne Hampson, Jehu J. Hanciles, Barry Hankins, Jennifer Haraguchi, Stanley S. Harakas, Anthony John Harding, Conrad L. Harkins, J. William Harmless, Marjory Harper, Amir Harrak, Joel F. Harrington, Mark W. Harris, Susan Ashbrook Harvey, Van A. Harvey, R. Chris Hassel, Jione Havea, Daniel Hawk, Diana L. Hayes, Leslie Hayes, Priscilla Hayner, S. Mark Heim, Simo Heininen, Richard P. Heitzenrater, Eila Helander, David Hempton, Scott H. Hendrix, Jan-Olav Henriksen, Gina Hens-Piazza, Carter Heyward, Nicholas J. Higham, David Hilliard, Norman A. Hjelm, Peter C. Hodgson, Arthur Holder, M. Jan Holton, Dwight N. Hopkins, Ronnie Po-chia Hsia, Po-Ho Huang, James Hudnut-Beumler, Jennifer S. Hughes, Leonard M. Hummel, Mary E. Hunt, Laennec Hurbon, Mark Hutchinson, Susan E. Hylen, Mary Beth Ingham, H. Larry Ingle, Dale T. Irvin, Jon Isaak, Paul John Isaak, Ada María Isasi-Díaz, Hans Raun Iversen, Margaret C. Jacob, Arthur James, Maria Jansdotter-Samuelsson, David Jasper, Werner G. Jeanrond, Renée Jeffery, David Lyle Jeffrey, Theodore W. Jennings, David H. Jensen, Robin Margaret Jensen, David Jobling, Dale A. Johnson, Elizabeth A. Johnson, Maxwell E. Johnson, Sarah Johnson, Mark D. Johnston, F. Stanley Jones, James William Jones, John R. Jones, Alissa Jones Nelson, Inge Jonsson, Jan Joosten, Elizabeth Judd, Mulambya Peggy Kabonde, Robert Kaggwa, Sylvester Kahakwa, Isaac Kalimi, Ogbu U. Kalu, Eunice Kamaara, Wayne C. Kannaday, Musimbi Kanyoro, Veli-Matti Kärkkäinen, Frank Kaufmann, Léon Nguapitshi Kayongo, Richard Kearney, Alice A. Keefe, Ralph Keen, Catherine Keller, Anthony J. Kelly, Karen Kennelly, Kathi Lynn Kern, Fergus Kerr, Edward Kessler, George Kilcourse, Heup Young Kim, Kim Sung-Hae, Kim Yong-Bock, Kim Yung Suk, Richard King, Thomas M. King, Robert M. Kingdon, Ross Kinsler, Hans G. Kippenberg, Cheryl A. Kirk-Duggan, Clifton Kirkpatrick, Leonid Kishkovsky, Nadieszda Kizenko, Jeffrey Klaiber, Hans-Josef Klauck, Sidney Knight, Samuel Kobia, Robert Kolb, Karla Ann Koll, Heikki Kotila, Donald Kraybill, Philip D. W. Krey, Yves Krumenacker, Jeffrey Kah-Jin Kuan, Simanga R. Kumalo, Peter Kuzmic, Simon Shui-Man Kwan, Kwok Pui-lan, André LaCocque, Stephen E. Lahey, John Tsz Pang Lai, Emiel Lamberts, Armando Lampe, Craig Lampe, Beverly J. Lanzetta, Eve LaPlante, Lizette Larson-Miller, Ariel Bybee Laughton, Leonard Lawlor, Bentley Layton, Robin A. Leaver, Karen Lebacqz, Archie Chi Chung Lee, Marilyn J. Legge, Hervé LeGrand, D. L. LeMahieu, Raymond Lemieux, Bill J. Leonard, Ellen M. Leonard, Outi Leppä, Jean Lesaulnier, Nantawan Boonprasat Lewis, Henrietta Leyser, Alexei Lidov, Bernard Lightman, Paul Chang-Ha Lim, Carter Lindberg, Mark R. Lindsay, James R. Linville, James C. Livingston, Ann Loades, David Loades, Jean-Claude Loba-Mkole, Lo Lung Kwong, Wati Longchar, Eleazar López, David W. Lotz, Andrew Louth, Robin W. Lovin, William Luis, Frank D. Macchia, Diarmaid N. J. MacCulloch, Kirk R. MacGregor, Marjory A. MacLean, Donald MacLeod, Tomas S. Maddela, Inge Mager, Laurenti Magesa, David G. Maillu, Fortunato Mallimaci, Philip Mamalakis, Kä Mana, Ukachukwu Chris Manus, Herbert Robinson Marbury, Reuel Norman Marigza, Jacqueline Mariña, Antti Marjanen, Luiz C. L. Marques, Madipoane Masenya (ngwan'a Mphahlele), Caleb J. D. Maskell, Steve Mason, Thomas Massaro, Fernando Matamoros Ponce, András Máté-Tóth, Odair Pedroso Mateus, Dinis Matsolo, Fumitaka Matsuoka, John D'Arcy May, Yelena Mazour-Matusevich, Theodore Mbazumutima, John S. McClure, Christian McConnell, Lee Martin McDonald, Gary B. McGee, Thomas McGowan, Alister E. McGrath, Richard J. McGregor, John A. McGuckin, Maud Burnett McInerney, Elsie Anne McKee, Mary B. McKinley, James F. McMillan, Ernan McMullin, Kathleen E. McVey, M. Douglas Meeks, Monica Jyotsna Melanchthon, Ilie Melniciuc-Puica, Everett Mendoza, Raymond A. Mentzer, William W. Menzies, Ina Merdjanova, Franziska Metzger, Constant J. Mews, Marvin Meyer, Carol Meyers, Vasile Mihoc, Gunner Bjerg Mikkelsen, Maria Inêz de Castro Millen, Clyde Lee Miller, Bonnie J. Miller-McLemore, Alexander Mirkovic, Paul Misner, Nozomu Miyahira, R. W. L. Moberly, Gerald Moede, Aloo Osotsi Mojola, Sunanda Mongia, Rebeca Montemayor, James Moore, Roger E. Moore, Craig E. Morrison O.Carm, Jeffry H. Morrison, Keith Morrison, Wilson J. Moses, Tefetso Henry Mothibe, Mokgethi Motlhabi, Fulata Moyo, Henry Mugabe, Jesse Ndwiga Kanyua Mugambi, Peggy Mulambya-Kabonde, Robert Bruce Mullin, Pamela Mullins Reaves, Saskia Murk Jansen, Heleen L. Murre-Van den Berg, Augustine Musopole, Isaac M. T. Mwase, Philomena Mwaura, Cecilia Nahnfeldt, Anne Nasimiyu Wasike, Carmiña Navia Velasco, Thulani Ndlazi, Alexander Negrov, James B. Nelson, David G. Newcombe, Carol Newsom, Helen J. 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Yee, Viktor Yelensky, Yeo Khiok-Khng, Gustav K. K. Yeung, Angela Yiu, Amos Yong, Yong Ting Jin, You Bin, Youhanna Nessim Youssef, Eliana Yunes, Robert Michael Zaller, Valarie H. Ziegler, Barbara Brown Zikmund, Joyce Ann Zimmerman, Aurora Zlotnik, Zhuo Xinping
- Edited by Daniel Patte, Vanderbilt University, Tennessee
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- The Cambridge Dictionary of Christianity
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- 05 August 2012
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- 20 September 2010, pp xi-xliv
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Duplicity Theory of Vision: From Newton to the Present, edited by B. Stabell and U. Stabell. 2009. Cambridge, Cambridge University Press.
- Gerald H. Jacobs
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- Visual Neuroscience / Volume 27 / Issue 1-2 / March 2010
- Published online by Cambridge University Press:
- 15 April 2010, pp. 75-76
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Photopigments of dogs and foxes and their implications for canid vision
- Gerald H. Jacobs, Jess F. Deegan II, Michael A. Crognale, John A. Fenwick
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- Visual Neuroscience / Volume 10 / Issue 1 / January 1993
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- 02 June 2009, pp. 173-180
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Electroretinogram (ERG) flicker photometry was used to examine the photopigment complements of representatives of four genera of Canid: domestic dog (Canis familiaris), Island gray fox (Urocyon littoralis), red fox (Vulpes vulpes), and Arctic fox (Alopex lagopus). These four genera share a common cone pigment complement; each has one cone pigment with peak sensitivity of about 555 nm and a second cone pigment with peak at 430–435 nm. These pigment measurements accord well with the conclusions of an earlier investigation of color vision in the dog, and this fact allows some predictions about color vision in the wild canids. An additional set of measurements place the peak of the dog rod pigment at about 508 nm.
Duplicity theory and ground squirrels: Linkages between photoreceptors and visual function
- Gerald H. Jacobs
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- Visual Neuroscience / Volume 5 / Issue 3 / September 1990
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- 02 June 2009, pp. 311-318
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The presence of rod and cone photorceptors has traditionally been linked to well-defined classes of visual capacity by the generalization known as duplicity theory. This paper summarizes results obtained from studies of vision and the visual system in ground squirrels (Spermophilus sp.) that reveal instances where structure/function linkages depart from expectations based in duplicity theory. The details of these exceptions are reviewed and their possible mechanisms discussed.
Spectral sensitivity of macaque monkeys measured with ERG flicker photometry
- Gerald H. Jacobs, Jess F. Deegan II
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- Visual Neuroscience / Volume 14 / Issue 5 / September 1997
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- 02 June 2009, pp. 921-928
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Macaque monkeys are widely used as a model species for investigations of the biology of human vision. Previous measurements suggest that the cone-based spectral sensitivity of these two primates is greatly similar, but perhaps not identical. We measured the photopic spectral sensitivity of 42 male macaque monkeys from two species (Macaca mulatto, M. fascicularis) using an objective index, electroretinogram flicker photometry. The variations among individuals and between the two species were very small and there was no evidence for any significant cone pigment polymorphism in this sample. There are small but systematic differences in spectral sensitivity between macaque monkeys and equivalently tested human subjects–the monkeys were slightly more sensitive to short wavelengths (<520 nm) and slightly less sensitive to wavelengths longer than this value. The results obtained from the curve fitting of standard photopigment absorption spectra to the spectral-sensitivity functions suggest that the difference between human and macaque monkey spectral sensitivity principally reflects differences in the relative proportions of the long- and middle-wavelength cones in the retinas of the two species.
Color vision in the dog
- Jay Neitz, Timothy Geist, Gerald H. Jacobs
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- Visual Neuroscience / Volume 3 / Issue 2 / August 1989
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- 02 June 2009, pp. 119-125
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The color vision of three domestic dogs was examined in a series of behavioral discrimination experiments. Measurements of increment-threshold spectral sensitivity functions and direct tests of color matching indicate that the dog retina contains two classes of cone photopigment. These two pigments are computed to have spectral peaks of about 429 nm and 555 nm. The results of the color vision tests are all consistent with the conclusion that dogs have dichromatic color vision.
Spectral sensitivity of cones in an ungulate
- Jay Neitz, Gerald H. Jacobs
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- Visual Neuroscience / Volume 2 / Issue 2 / February 1989
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- 02 June 2009, pp. 97-100
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Ungulates have been classified as having arrhythmic eyes in the sense that they contain features appropriate both to diurnal and nocturnal life. The former is typically associated with multiple classes of cones and a color-vision capacity. To see if an arrhythmic animal has these features, the number of cone classes was determined and the spectra of these cones were measured in a common ungulate, the domestic pig (Sus scrofa). Examination with electroretinogram (ERG) flicker photometry revealed the presence of two classes of cones in the pig's eye having average maximum sensitivity (λmax) at 439 nm and 556 nm, respectively. This ungulate thus has the requisite retinal basis for dichromatic color vision.
Regional variations in the relative sensitivity to UV light in the mouse retina
- Jack B. Calderone, Gerald H. Jacobs
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- Journal:
- Visual Neuroscience / Volume 12 / Issue 3 / May 1995
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- 02 June 2009, pp. 463-468
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About 3% of all mouse photoreceptors are cones. An earlier electrophysiological study indicated that there were two classes of cone in the mouse retina having peak sensitivities (λmax) of about 360 nm and 511 nm. Recent immunocytochemical results show there are two types of cones that have distinctive regional segregation patterns. We used regional stimulation of the retina in conjunction with electroretinogram (ERG) flicker photometry to see if the two cone types identified electrophysiologically are regionalized in a fashion suggested by the anatomical results. We find they are. Relative sensitivity to ultraviolet and visible light stimulation qualitatively parallels that predicted by immunocytochemical labelling. One result of this remarkable regionalization of cone types is that the mouse retina is relatively more sensitive to ultraviolet light stimulation when that light is directed toward the ventral half of the retina.
Behavioral and electrophysiological sensitivity to temporally modulated visual stimuli in the ground squirrel
- Michael A. Crognale, Gerald H. Jacobs
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- Visual Neuroscience / Volume 6 / Issue 6 / June 1991
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- 02 June 2009, pp. 593-606
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Behavioral and electrophysiological methods were used to measure sensitivity to flickering lights in a dichromatic species, the California ground squirrel (Spermophilus beecheyi). Discrimination tests were used to determine spectral sensitivity at stimulus frequencies from 5–50 Hz and increment threshold spectral sensitivity. The contributions of retinal mechanisms to these capacities were assessed by recording the responses of optic nerve fibers to temporally modulated monochromatic lights. In the ground squirrel, as in the human, the shape of the spectral-sensitivity function depends on the temporal frequency of the stimulus. Results from single-unit recording show that all of the classes of optic nerve fibers in the ground squirrel are highly phase-locked to the stimulus for modulation rates as high as 50 Hz. Neither the responses of photoreceptors nor any class of optic nerve fiber can singly account for the behavioral results. The electrophysiological results are also counter to models which propose that temporally dependent changes in the spectral sensitivity of spectrally opponent fibers account for the behavior. The temporal resolution of the optic nerve fibers exceeds that of the behaving animal suggesting that retinal mechanisms do not limit behavioral temporal resolution.
Primate color vision: A comparative perspective
- GERALD H. JACOBS
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- Journal:
- Visual Neuroscience / Volume 25 / Issue 5-6 / September 2008
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- 01 September 2008, pp. 619-633
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Thirty years ago virtually everything known about primate color vision derived from psychophysical studies of normal and color-defective humans and from physiological investigations of the visual system of the macaque monkey, the most popular of human surrogates for this purpose. The years since have witnessed much progress toward the goal of understanding this remarkable feature of primate vision. Among many advances, investigations focused on naturally occurring variations in color vision in a wide range of nonhuman primate species have proven to be particularly valuable. Results from such studies have been central to our expanding understanding of the interrelationships between opsin genes, cone photopigments, neural organization, and color vision. This work is also yielding valuable insights into the evolution of color vision.
Naturalistic color discriminations in polymorphic platyrrhine monkeys: Effects of stimulus luminance and duration examined with functional substitution
- MICKEY P. ROWE, GERALD H. JACOBS
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- Journal:
- Visual Neuroscience / Volume 24 / Issue 1 / January 2007
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- 11 April 2007, pp. 17-23
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X-linked photopigment polymorphism produces six different color vision phenotypes in most species of New World monkey. In the subfamily Callitrichinae, the three M/L alleles underlying these different phenotypes are present at unequal frequencies suggesting that selective pressures other than heterozygous-advantage operate on these alleles. Earlier we investigated this hypothesis with functional substitution, a technique using a computer monitor to simulate colors as they would appear to humans with monkey visual pigments (Visual Neuroscience21:217–222, 2004). The stimuli were derived from measurements of ecologically relevant fruit and foliage. We found that discrimination performance depended on the relative spectral positioning of the substituted M and L pigment pair. Here we have undertaken a systematic examination of two simulation parameters—test field luminance and stimulus duration. Discriminability of the fruit colors depended on which phenotype was simulated but only at short stimulus durations and/or low luminances. Under such conditions, phenotypes with the larger pigment peak separations performed better. At longer durations and higher luminances, differences in performance across different substitutions tended to disappear. The stimuli used in this experiment were analyzed with several color discrimination models. There was limited agreement among the predictions made by these models regarding the capabilities of animals with different pigment pairs and none predicted the dependence of discrimination on changes in luminance and stimulus duration.
L and M cone proportions in polymorphic New World monkeys
- GERALD H. JACOBS, GARY A. WILLIAMS
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- Journal:
- Visual Neuroscience / Volume 23 / Issue 3-4 / May 2006
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- 06 September 2006, pp. 365-370
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Platyrrhine monkeys typically have only a single X-chromosome opsin gene. Alleles of this gene code for multiple versions of middle- to long-wavelength cone photopigments. X-chromosome inactivation provides heterozygous females with a retinal mosaic of cones containing either of two types of M and L pigment, thus establishing the photopigment basis for trichromatic color vision. This study examined the proportions of L and M cones created by this process. For that purpose, electroretinogram flicker photometry was used to obtain complete spectral sensitivity functions from 60 heterozygous female monkeys drawn from seven genera of platyrrhine monkeys. To obtain estimates of cone proportions, these functions were subsequently fit with linear combinations of L and M cone fundamentals that were derived from similar recordings made on conspecific animals having only one type of M/L pigment. Consistent with a random X-chromosome inactivation process, the average L:M cone weighting across the sample was close to unity. At the same time, there were significant individual variations in L:M cone proportions. The genesis of this variation and its implications for seeing are discussed.
Rod and cone function in coneless mice
- GARY A. WILLIAMS, KRISTIN A. DAIGLE, GERALD H. JACOBS
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- Journal:
- Visual Neuroscience / Volume 22 / Issue 6 / November 2005
- Published online by Cambridge University Press:
- 03 February 2006, pp. 807-816
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Transgenic coneless mice were initially developed to study retinal function in the absence of cones. In coneless mice created by expressing an attenuated diphtheria toxin under the control of flanking sequences from the human L-cone opsin gene, a small number of cones (3–5% of the normal complement) survive in a retina that otherwise appears structurally quite normal. These cones predominantly (∼87% of the total) contain UV-sensitive photopigment. ERG recordings, photoreceptor labeling, and behavioral measurements were conducted on coneless and wild-type mice to better understand how the nature of this alteration in receptor complement impacts vision. Signals from the small residual population of UV cones are readily detected in the flicker ERG where they yield signal amplitudes at saturation that are roughly proportional to the number of surviving cones. Behavioral measurements show that rod-based vision in coneless mice does not differ significantly from that of wild-type mice, nor does their rod system show any evidence of age-related deterioration. Coneless mice are able to make accurate rod-based visual discriminations at light levels well in excess of those required to reach cone threshold in wild-type mice.
Cone pigment polymorphism in New World monkeys: Are all pigments created equal?
- MICKEY P. ROWE, GERALD H. JACOBS
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- Journal:
- Visual Neuroscience / Volume 21 / Issue 3 / May 2004
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- 05 April 2005, pp. 217-222
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Most platyrrhine monkeys have a triallelic M/L opsin gene polymorphism that underlies significant individual variations in color vision. A survey of the frequencies of these polymorphic genes suggests that the three alleles occur with equal frequency among squirrel monkeys (subfamily Cebinae), but are not equally frequent in a number of species from the subfamily Callitrichinae. This departure from equal frequency in the Callitrichids should slightly increase the ratio of dichromats to trichromats in the population and significantly alter the relative representation of the three possible dichromatic and trichromatic phenotypes. A particular feature of the inequality is that it leads to a relative increase in the number of trichromats whose M/L pigments have the largest possible spectral separation. To assess whether these trichromatic phenotypes are equally well equipped to make relevant visual discriminations, psychophysical experiments were run on human observers. A technique involving the functional substitution of photopigments was used to simulate the discrimination between fruits among a background of leaves. The goal of the simulation was to reproduce in the cones of human observers excitations equivalent to those produced in monkey cones as the animals view fruit. Three different viewing conditions were examined involving variations in the relative luminances of fruit and leaves and the spectrum of the illuminant. In all cases, performance was best for simulated trichromacies including M/L pigments with the largest spectral separation. Thus, the inequality of opsin gene frequency in Callitrichid monkeys may reflect adaptive pressures.
Spectral properties and retinal distribution of ferret cones
- JACK B. CALDERONE, GERALD H. JACOBS
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- Journal:
- Visual Neuroscience / Volume 20 / Issue 1 / January 2003
- Published online by Cambridge University Press:
- 13 March 2003, pp. 11-17
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The spectral mechanisms of the ferret (Mustela putorious furo) were studied with electroretinogram (ERG) flicker photometry. Variations in adaptation state and flicker rate were used to define corneally based spectral sensitivities for the three classes of receptor present in the retina of this mustelid—rods (λmax = 505 nm), S cones (430 nm), and L cones (558 nm). The retinal distributions of the two classes of cone were determined using opsin antibody labeling. Ferret retinas contain a total of about 1.3 million cones with L cones outnumbering S cones in a ratio of approximately 14:1. ERGs were also recorded using 18.75-Hz flickering stimuli that were designed to isolate signals from individual cone classes. The contrast/response functions for signals originating from both S and L cones were linear over low-to-moderate levels of contrast, but with greatly different slopes for the two cone types. The L:S contrast gain ratio derived from a comparison of these slopes, as well as inferences drawn from another experiment in which responses to various combinations of L- and S-cone activation were analyzed, suggest that contributions of these two cone types to the flicker ERG have a relative weighting of about 4:1 to 5:1 (L/S).