Dan Janzen and Winnie Hallwachs, at the American Museum of Natural History, 1998

Daniel Hunt Janzen (b. 1939 in Milwaukee, Wisconsin, USA) is an evolutionary ecologist, naturalist, and conservationist. He divides his time between his professorship in biology at the University of Pennsylvania (Philadelphia, USA), where he has been since 1976, and his research and field work in Costa Rica, where he is an ad honorem (without remuneration) technical advisor for two long-term and long-range projects, which he conceived and initiated in the early 1970's: Area de Conservación Guanacaste, probably the oldest, largest and most successful habitat restoration project in the world, 1.430 km², located just south of the Costa Rica-Nicaragua border, between the Pacific Ocean and the Cordillera de Talamanca; and the Instituto Nacional de Biodiversidad (Costa Rican national biodiversity institute), a research organisation that has taken the task of inventorying, cataloguing and describing the country's gigantic natural endowment. Image File history File linksMetadata Dan_Winnie_cropped. ... Image File history File linksMetadata Dan_Winnie_cropped. ... This article is about Milwaukee in Wisconsin. ... This article does not cite its references or sources. ... The University of Pennsylvania (or Penn[3][4]) is a private, nonsectarian research university located in Philadelphia, Pennsylvania. ... Nickname: City of Brotherly Love, Philly, the City That Loves You Back, the Quaker City, The Birthplace of America Motto: Philadelphia maneto - Let brotherly love continue Location in Pennsylvania Coordinates: Country United States State Pennsylvania County Philadelphia Founded October 27, 1682 Incorporated October 25, 1701 Mayor John F. Street (D... The Area de Conservación Guanacaste, is a World Heritage Site in the northwestern part of Costa Rica, which comprises Santa Rosa, Guanacaste, Rincón de la Vieja National Parks and the Junquillal Bay Wildlife Refuge. ... The Cordillera de Talamanca is a range of mountains that lies on the border between Costa Rica and Panama. ...

Janzen obtained his BS degree from the University of Minnesota, Minneapolis in 1961, and his Ph.D. from the University of California, Berkeley, in 1965. In 1964 he attended as a student a two-month course in tropical biology taught in several field sites throughout Costa Rica, offered by the Organization for Tropical Studies (OTS), a consortium of several North American and Costa Rican universities, he went back in 1965 as an instructor and has lectured in at least one of the three yearly courses, every year since. Before joining the faculty at the University of Pennsylvania he taught at the University of Kansas (1965-1968), the University of Chicago (1969-72) and at the University of Michigan (1972-76). Janzen has also held teaching positions in Venezuela (Universidad de Oriente, Cumaná in 1965-66; Universidad de los Los Andes, Mérida in 1973), and in Puerto Rico (Universidad de Puerto Rico, Río Piedras, 1969). From these teaching positions, because of his continuous association with OTS, through his numerous publications and mostly from his exemplary dedication, Janzen has been in close contact and influenced the thinking and ideas of just about every researcher and student of tropical ecology and conservation in the western hemisphere during the last 40 years. Washington Avenue Bridge at night The University of Minnesota, Twin Cities, almost always abbreviated U of M, and sometimes referred to as The U by locals, is the oldest and largest part of the University of Minnesota system. ... This article is about the city in Minnesota. ... This article or section does not cite its references or sources. ... The University of California, Berkeley (also known as UC Berkeley, Berkeley, Cal, and by other names, see below) is the oldest and flagship campus of the ten-campus University of California system. ... The University of Pennsylvania (or Penn[3][4]) is a private, nonsectarian research university located in Philadelphia, Pennsylvania. ... The University of Kansas (often referred to as KU or Kansas) is an institution of higher learning located in Lawrence, Kansas. ... 1965 (MCMLXV) was a common year starting on Friday (the link is to a full 1965 calendar). ... 1968 (MCMLXVIII) was a leap year starting on Monday (the link is to a full 1968 calendar). ... The University of Chicago is a private university located principally in the Hyde Park neighborhood of Chicago. ... 1969 (MCMLXIX) was a common year starting on Wednesday (the link is to a full 1969 calendar). ... 1972 (MCMLXXII) was a leap year starting on Saturday. ... The University of Michigan is a coeducational public research university in the U.S. state of Michigan. ... 1972 (MCMLXXII) was a leap year starting on Saturday. ... 1976 (MCMLXXVI) was a leap year starting on Thursday. ... The University of Oriente Venezuela (Spanish: Universidad de Oriente Venezuela, UDO) is a university located in Eastern Venezuela. ... A traditional fishermans boat called Peñero at Mochimas National Park. ... Funded as: Santiago de los Caballeros de Mérida Motto of the city: La ciudad de los caballeros Estado Mérida Municipio Municipio Libertador Alcalde Carlos León (2004 – 2008) Surface 25 km² (aprox. ... The University of Puerto Rico (UPR) is the university system of Puerto Rico. ... Río Piedras was a town in Puerto Rico which was absorbed by the city of San Juan and is now one of its districts. ...

Research, from theory to praxis and back to theory

Janzen's work exemplifies the dialectic method of research applied to the biology of the natural world. For him it has not been the passive analysis of documents and data about ecological processes in order to formulate theories, but rather the active creation of life size scenarios of ecological change and their careful and meticulous documentation from which he then formulates theories which inspire new grand experiments in an ever expanding spiral of knowledge based on the keen observation of nature. The following three sections are an attempt to synthesise the three main themes of his life long quest and work. In classical philosophy, dialectic (Greek: διαλεκτική) is an exchange of propositions (theses) and counter-propositions (antitheses) resulting in a synthesis of the opposing assertions, or at least a qualitative transformation in the direction of the dialogue. ...

Coevolution of plants and animals

[In preparation]

• Coevolution of a mutualistic system in New World tropics between species of Acacia (Mimosoideae; Leguminosae), v. gr., Acacia cornigera, and the ant Pseudomyrmex ferruginea (Formicidae). Acacia spp in the Neotropics are protected by ants against defoliation; for this, the ants are rewarded by means of special organs and physiology that Acacia has evolved. Also Cecropia spp, different plant, different ant, same story! 1
• Spondias mombin (Anacardiaceae) lost its megafauna seed dispersors in the Pleistocene. Between fire in open pastures and seed predation by brochid beetles in closed canopy forest S. mombindoes not stand a chance. But,today, in Guanacaste, seeds are dispersed by white tailed deer (Odocoileus virginianus) and some 15 other mammals, that feed mostly in forest edges, where bruchids are less likely to find the seeds and fires are not so frequent. 2

Species About 1,300; see List of Acacia species Acacia tree in the Serengeti, Tanzania Acacia is a genus of shrubs and trees of Gondwanian origin belonging to the Subfamily Mimosoideae of the family Fabaceae, first described from Africa by Linnaeus in 1773. ... Infrafamilies Acacieae Ingeae Mimoseae Mimozygantheae Parkieae The Mimosoideae is a subfamily of the Family Fabaceae characterized by flowers with small petals and numerous prominent stamens. ... Leguminosae is one of two scientific names allowed for a plant family of close to twenty thousands species. ... Subfamilies Formicomorph subfamilies Aneuretinae Dolichoderinae Formicinae - e. ... The Acropolis of Athens, seen from the hill of the Pnyx to the west The Acropolis of Athens, seen from the north, with the restored Stoa of Attalus in the foreground The south wall of the Acropolis of Athens, seen from the Theatre of Dionysus The Acropolis of Athens, seen... Binomial name Spondias mombin L. Synonyms Spondias lutea L. Spondias mombin is a species of flowering plant in the family Anacardiaceae. ... Genera See text Anacardiaceae is a family of flowering plants bearing fruits that are drupes. ... The Pleistocene epoch (IPA: ) is part of the geologic timescale. ... Seed predation includes any process inflicted on a plant’s seeds by an animal that results in the inviability of the seed. ...

Tropical habitat restoration

[In preparation]

Tropical dry forests are the world most threatened of forest ecosystems. In middle America there were 550.000 km² of dry forests at the beginning of the 16th century; today, less than 0,08% (440 km² ) remains, they have been cleared, burnt and replaced by pastures for cattle raising, at an ever faster rate during the last 500 years. However, beginning in the early 1970's, Janzen dreamed a most fantastic project, to grow back some 700 km² of natural, pre-Colombian habitat in Guanacaste, in order to integrate 4 different national parks which together house at least 15 different biotopes, (mangroves, dry forest and shrubs, ephemeral, rainy season, and permanent streams, fresh water and littoral swamps, evergreen rain- and cloud forests…) and ca. 4% from world's plant, mammals, birds, reptiles, amphibians, fishes and insects diversity, all within an area less than 1.500 km². This is Área de Conservación Guanacaste (ACG). 3 Trinidad and Tobago dry forest on Chacachacare showing the dry-season deciduous nature of the vegetation The tropical and subtropical dry broadleaf forest biome, also known as tropical dry forest, is located at tropical and subtropical latitudes. ... A biotope is an area of uniform environmental (physical) conditions providing habitat(s) for a specific assemblage of plants and animals. ... Guanacaste National Park is a fifty acre (200,000 m²) park in central Belize. ...

Habitat restoration is not a simple matter, not only one should fight against hundreds of years of ecological degradation, manifested in the form of altered drainage patterns, hard to eradicate pastures, compacted soils, exhausted seed banks, diminished adult and propagule stocks, proliferation of fire resistant and unpalatable weeds from the old world tropics and sub-tropics, et cetera, but also one should face the difficulties of changing a culture which coevolved with, profited from and can become miserable with such a system. For this reason ACG was conceived as a cultural restoration project as well, which, to paraphrase its natural counterpart, ought to be grown as well. ACG rests on three complementary processes that integrate experimentation, habitat restoration and cultural development, to speed up succession:

• Active restoration, artificial dispersal of propagules from plant species native to the Guanacaste habitats
• Passive restoration by means of fire, poaching and hervivory control
• Ecological education and sensibilisation

Sustainable ecosystem utilisation

[In preparation]

Agriculture in the tropics - "Tropical Agroecosystems," Science, 1973, paper.

Honorary distinctions

Janzen has been subject to recognition very many times in USA, as well as in Europe and Latin America; the monetary endowments of these prises have been invested in the trust fund of the ACG or another of his conservation's projects in Costa Rica; amongst the 19 prises and distinctions, the following are the most important:

• 1975 Gleason Award, American Botanical Society
• 1984 Crafoord Prize: Coevolutionary ecology. Swedish Royal Academy of Sciences
• 1985 Distinguished Teaching Award, University of Pennsylvania
• 1987 The Berkeley Citation for Distinguished Achievement and Notable Service to the university
• 1987 Hijo Ilustre de Guanacaste (awarded by the Governor of Guanacaste province)
• 1987 "Global 500" Roll of Honour, UNEP
• 1989 MacArthur Fellowship
• 1989 Joseph Leidy Medal, Philadelphia Academy of Natural Sciences
• 1991 Founder's Council Award of Merit, Field Museum of Natural History
• 1992 Member, National Academy of Sciences, USA
• 1993 Award for Improvement of Costa Rican Quality of Life, Universidad de Costa Rica (co award with W. Hallwachs).
• 1994 Silver Medal Award, International Society of Chemical Ecology.
• 1995 Conservation Society Award.
• 1996 Honorary Doctor of Science, University of Minnesota.
• 1996 Thomas G. and Louise E. DiMaura Endowed Term Chair, University of Pennsylvania
• 1997 Kyoto Prize (Basic Sciences Field), Inimori Foundation
• 2002 Albert Einstein World Award for Science, Consejo Cultural Mundial, (Mexico)

1975 (MCMLXXV) was a common year starting on Wednesday. ... 1984 (MCMLXXXIV) was a leap year starting on Sunday of the Gregorian calendar. ... The Crafoord Prize was established in 1980 by Holger Crafoord, the inventor of the artificial kidney, and his wife Anna-Greta Crafoord. ... 1985 (MCMLXXXV) was a common year starting on Tuesday of the Gregorian calendar. ... The University of Pennsylvania (or Penn[3][4]) is a private, nonsectarian research university located in Philadelphia, Pennsylvania. ... 1987 (MCMLXXXVII) was a common year starting on Thursday of the Gregorian calendar. ... The University of California, Berkeley (also known as UC Berkeley, Berkeley, Cal, and by other names, see below) is the oldest and flagship campus of the ten-campus University of California system. ... 1987 (MCMLXXXVII) was a common year starting on Thursday of the Gregorian calendar. ... Guanacaste is a province of Costa Rica. ... 1987 (MCMLXXXVII) was a common year starting on Thursday of the Gregorian calendar. ... Klaus Töpfer, UNEP Exec. ... 1989 (MCMLXXXIX) was a common year starting on Sunday of the Gregorian calendar. ... The John D. and Catherine T. MacArthur Foundation is a private, independent grantmaking institution. ... 1989 (MCMLXXXIX) was a common year starting on Sunday of the Gregorian calendar. ... The Academy of Natural Sciences in Philadelphia was founded in 1812 to expand knowledge of the natural world. ... 1991 (MCMXCI) was a common year starting on Tuesday of the Gregorian calendar. ... Field Museum of Natural History, Chicago The Field Museum of Natural History, in Chicago, Illinois, USA, sits on Lake Shore Drive next to Lake Michigan, part of a scenic complex known as Museum Campus Chicago. ... 1992 (MCMXCII) was a leap year starting on Wednesday. ... President Harding and the National Academy of Sciences at the White House, Washington, DC, April 1921 The National Academy of Sciences (NAS) is a corporation in the United States whose members serve pro bono as advisers to the nation on science, engineering, and medicine. ... 1993 (MCMXCIII) was a common year starting on Friday of the Gregorian calendar and marked the Beginning of the International Decade to Combat Racism and Racial Discrimination (1993-2003). ... The University of Costa Rica (in Spanish, Universidad de Costa Rica, abbreviated UCR) is a public university in the Republic of Costa Rica, in Central America. ... 1994 (MCMXCIV) was a common year starting on Saturday of the Gregorian calendar, and was designated as the International Year of the Family and the International Year of the Sport and the Olympic Ideal by United Nations. ... 1995 (MCMXCV) was a common year starting on Sunday of the Gregorian calendar. ... 1996 (MCMXCVI) was a leap year starting on Monday of the Gregorian calendar, and was designated the International Year for the Eradication of Poverty. ... Washington Avenue Bridge at night The University of Minnesota, Twin Cities, almost always abbreviated U of M, and sometimes referred to as The U by locals, is the oldest and largest part of the University of Minnesota system. ... 1996 (MCMXCVI) was a leap year starting on Monday of the Gregorian calendar, and was designated the International Year for the Eradication of Poverty. ... The University of Pennsylvania (or Penn[3][4]) is a private, nonsectarian research university located in Philadelphia, Pennsylvania. ... 1997 (MCMXCVII) was a common year starting on Wednesday of the Gregorian calendar. ... For album titles with the same name, see 2002 (album). ... The Albert Einstein World Award for Science is a yearly award given by the World Cultural Council as a means of recognition, and as an incentive to scientific and technological research and development, with special consideration for researches which have brought true benefit and well being to mankind. The award...

Publications

[In preparation]

More than 300 papers mostly on tropical habitats and organisms.

References

1. Janzen, D. H. 1966. Coevolution of mutualism between ants and acacias in Central America. Evolution: 20(3) 249-275
2. Janzen, D. H. 1985. Spondias mombin is Culturally Deprived in Megafauna-Free Forest. Journal of Tropical Ecology 1:131-155.
3. Janzen, D. H. 1986. Guanacaste National Park: Tropical Ecological and Cultural Restoration. Editorial Universidad Estatal a Distancia/ FundaciónTinker/Fundación Parque Nacionales/103 pp. San José, Costa Rica.

External links

• Faculty page at University of Pennsylvania
• Third World Conservation: It's ALL Gardening recorded April 2004 at the Long Now Foundation
• Restoration ecologist interview with Omni April 1993