366
P. 9. MEADOWS AND J. I. OAMPBELL
must therefore await a detailed understanding of these rules and of
their interactions. The authors have speculated that this might also
come from a predictive mathematics which would correlate behaviour
with distribution by matching the classical concepts of probability and
statistics, perhaps expressed pictorially by a series of response surfaces
(Box and Wilson, 1951 ; Box, 1954), with the advanced cybernetics and
computer technology at present available. Although concerned with the
modelling of field distributions themselves rather than with models
which interpret field distribution in terms of habitat selection, the
works of Skellam (1951), Watt (1968), Siniff and Jessen (1969) and
Kitching (1971) illustrate both the benefits and the limitations of the
approach.
One of the functions of the present review has been to outline
areas where more research is needed. It is really quite surprising, for
instance, that there are so few comprehensive studies on any one species,
that so little is known of habitat selection by sublittoral benthic
invertebrates in the sea, that we know nothing of the reactions of
freshwater invertebrates to the microbial fauna of sediments, and that
conditioning, the genetics of habitat selection, and the colonization of
new habitats in aquatic environments have received so little attention.
In the long term, studies on habitat selection, in other words on the
behaviour which results in animals being found in particular places a t
particular times, are bound to be of great economic importance.
Before fish can be farmed efficiently or molluscs and crustaceans
cultured successfully, their choice of habitats, their preferred foods,
their avoidance of predators and their gregariousness must be
understood in detail.
x. SUMMARY
1. The present review attempts to explain the field distribution of
marine and freshwater invertebrates in terms of their behaviour and
habitat selection.
2. Habitat selection is considered firstly in relation to the nonbiological, or chemical and physical, environment.
(a) Intertidal invertebrates react to a wide range of environmental
variables which will tend to restrict them to localized areas of the
shore. Their responses to light, to gravity and pressure, and to
the particle size of sediments are fairly well documented, but less
is known of their salinity, temperature, or humidity preferences,
or of their responses to anaerobic conditions. The depth of sediments, their packing characteristics, and their degree of dryness
appear to be important to the few burrowing invertebrates that
P. 9. MEADOWS AND J. I. OAMPBELL
must therefore await a detailed understanding of these rules and of
their interactions. The authors have speculated that this might also
come from a predictive mathematics which would correlate behaviour
with distribution by matching the classical concepts of probability and
statistics, perhaps expressed pictorially by a series of response surfaces
(Box and Wilson, 1951 ; Box, 1954), with the advanced cybernetics and
computer technology at present available. Although concerned with the
modelling of field distributions themselves rather than with models
which interpret field distribution in terms of habitat selection, the
works of Skellam (1951), Watt (1968), Siniff and Jessen (1969) and
Kitching (1971) illustrate both the benefits and the limitations of the
approach.
One of the functions of the present review has been to outline
areas where more research is needed. It is really quite surprising, for
instance, that there are so few comprehensive studies on any one species,
that so little is known of habitat selection by sublittoral benthic
invertebrates in the sea, that we know nothing of the reactions of
freshwater invertebrates to the microbial fauna of sediments, and that
conditioning, the genetics of habitat selection, and the colonization of
new habitats in aquatic environments have received so little attention.
In the long term, studies on habitat selection, in other words on the
behaviour which results in animals being found in particular places a t
particular times, are bound to be of great economic importance.
Before fish can be farmed efficiently or molluscs and crustaceans
cultured successfully, their choice of habitats, their preferred foods,
their avoidance of predators and their gregariousness must be
understood in detail.
x. SUMMARY
1. The present review attempts to explain the field distribution of
marine and freshwater invertebrates in terms of their behaviour and
habitat selection.
2. Habitat selection is considered firstly in relation to the nonbiological, or chemical and physical, environment.
(a) Intertidal invertebrates react to a wide range of environmental
variables which will tend to restrict them to localized areas of the
shore. Their responses to light, to gravity and pressure, and to
the particle size of sediments are fairly well documented, but less
is known of their salinity, temperature, or humidity preferences,
or of their responses to anaerobic conditions. The depth of sediments, their packing characteristics, and their degree of dryness
appear to be important to the few burrowing invertebrates that