The
SLOSS Debate was a debate in
ecologyEcology is the interdisciplinary scientific study of the interactions between organisms and the interactions of these organisms with their environment....
and
conservation biologyConservation biology is the scientific study of the nature and status of Earth's biodiversity with the aim of protecting species, their habitats, and ecosystems from excessive rates of extinction. It is an interdisciplinary subject drawing on sciences, economics, and the practice of natural...
during the 1970s and 1980s as to whether
Single
Large
or
Several
Small (SLOSS) reserves were a superior means of conserving
biodiversityBiodiversity is the variation of life forms within a given ecosystem, biome, or for the entire Earth. Biodiversity is often used as a measure of the health of biological systems...
in a
fragmented habitatHabitat fragmentation is a process of environmental change important in evolution and conservation biology. As the name implies, it describes the emergence of discontinuities in an organism's preferred environment...
.
In 1975
Jared DiamondJared Mason Diamond is an American scientist and nonfiction author whose work draws from a variety of fields. He is currently Professor of Geography and Physiology at UCLA...
suggested some "rules" for the design of protected areas, based on
Robert MacArthurRobert Helmer MacArthur was an American ecologist who made a major impact on many areas of community and population ecology....
and
E. O. WilsonEdward Osborne Wilson is an American biologist, researcher , theorist , naturalist and author. His biological specialty is myrmecology, a branch of entomology....
's
Theory of Island BiogeographyIsland biogeography is a field within biogeography that attempts to establish and explain the factors that affect the species richness of natural communities. The theory was developed to explain species richness of actual islands. It has since been extended to mountains surrounded by deserts, lakes...
. One of his suggestions was that a single large reserve was preferable to several smaller reserves whose total areas were equal to the larger.
The
SLOSS Debate was a debate in
ecologyEcology is the interdisciplinary scientific study of the interactions between organisms and the interactions of these organisms with their environment....
and
conservation biologyConservation biology is the scientific study of the nature and status of Earth's biodiversity with the aim of protecting species, their habitats, and ecosystems from excessive rates of extinction. It is an interdisciplinary subject drawing on sciences, economics, and the practice of natural...
during the 1970s and 1980s as to whether
Single
Large
or
Several
Small (SLOSS) reserves were a superior means of conserving
biodiversityBiodiversity is the variation of life forms within a given ecosystem, biome, or for the entire Earth. Biodiversity is often used as a measure of the health of biological systems...
in a
fragmented habitatHabitat fragmentation is a process of environmental change important in evolution and conservation biology. As the name implies, it describes the emergence of discontinuities in an organism's preferred environment...
.
In 1975
Jared DiamondJared Mason Diamond is an American scientist and nonfiction author whose work draws from a variety of fields. He is currently Professor of Geography and Physiology at UCLA...
suggested some "rules" for the design of protected areas, based on
Robert MacArthurRobert Helmer MacArthur was an American ecologist who made a major impact on many areas of community and population ecology....
and
E. O. WilsonEdward Osborne Wilson is an American biologist, researcher , theorist , naturalist and author. His biological specialty is myrmecology, a branch of entomology....
's
Theory of Island BiogeographyIsland biogeography is a field within biogeography that attempts to establish and explain the factors that affect the species richness of natural communities. The theory was developed to explain species richness of actual islands. It has since been extended to mountains surrounded by deserts, lakes...
. One of his suggestions was that a single large reserve was preferable to several smaller reserves whose total areas were equal to the larger. Since
species richnessSpecies richness is the number of different species in a given area. It is represented in equation form as .Typically, species richness is used in conservation studies to determine the sensitivity of ecosystems and their resident species. The actual number of species calculated alone is largely an...
increases with
habitatA habitat is an ecological or environmental area that is inhabited by a particular animal and plant species...
area, a larger block of habitat would support more species than any of the smaller blocks. This idea was popularised by many other ecologists, and has been incorporated into most standard textbooks in conservation biology, and was used in real-world conservation planning. This idea was challenged by Wilson's former student
Daniel SimberloffDaniel Simberloff is a biologist and ecologist who earned his Ph.D. from Harvard University in 1969.Simberloff started his studies in ecology as a student of the biologist E. O. Wilson, one of the co-authors of the theory of Island biogeography . For his Ph.D...
who pointed out that this idea relied on the assumption that smaller reserves had a
NestedNestedness is a measure of order in an ecological system, referring to the order in which the number of species is related to area or other factors. The more a system is "nested" the more it is organised....
species composition - it assumed that each larger reserve had all the species presented in any smaller reserve. If the smaller reserves had unshared species, then it was possible that two smaller reserves could have more species than a single large reserve. Simberloff and Abele expanded their argument in subsequent paper in the prestigious journal
The American Naturalist stating neither ecological theory nor empirical data exist to support the hypothesis that subdividing a nature reserve would increase extinction rates, basically negating Diamond as well as MacArthur and Wilson. Bruce A. Wilcox and Dennis L. Murphy responded to this paper in the same journal pointing out flaws in their argument while providing a comprehensive definition of
habitat fragmentationHabitat fragmentation is a process of environmental change important in evolution and conservation biology. As the name implies, it describes the emergence of discontinuities in an organism's preferred environment...
. Wilcox and Murphy also argued that habitat fragmentation likely is the major threat to the loss of global biological diversity. This helped set the stage for fragmentation research as an important area of
conservation biologyConservation biology is the scientific study of the nature and status of Earth's biodiversity with the aim of protecting species, their habitats, and ecosystems from excessive rates of extinction. It is an interdisciplinary subject drawing on sciences, economics, and the practice of natural...
. The SLOSS debate ensued as to the extent to which smaller reserves shared species with one another, leading to the development of
nested subset theory by
Bruce PattersonBruce Patterson was a Scottish cricketer. He took his first two wickets in a competition in June 2004 against Holland. He participated in three One-day internationals in May 1999 and played List A cricket from 1988 to 2002...
and Wirt Atmar in the 1980s and to the establishment of the
Biological Dynamics of Forest Fragments ProjectThe Biological Dynamics of Forest Fragments Project is a large-scale ecological experiment looking at the effects of habitat fragmentation on tropical rainforest. The experiment, which was established in 1979 is located near Manaus, in the Brazilian Amazon...
(BDFFP) near
ManausManaus is a city in Brazil, the capital of the state of Amazonas. It is situated at the confluence of the Negro and Solimões rivers. It is the most populous city of Amazonas, according to the statistics of Brazilian Institute of Geography and Statistics, and is a popular ecotourism destination....
,
BrazilBrazil , officially the Federative Republic of Brazil , is a country in South America. It is the fifth largest country by geographical area, occupying nearly half of South America, the fifth most populous country, and the fourth most populous democracy in the world. Bounded by the Atlantic Ocean...
in 1980 by
Thomas LovejoyDr. Thomas Eugene Lovejoy III is chief biodiversity adviser to the president of the World Bank, senior adviser to the president of the United Nations Foundation, and president of the Heinz Center for Science,Economics, and the Environment...
.