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WILLIAM MACNAE
these trees they are associated with coccids and other bugs. Way
(1954b) recorded that Oecophylla transplants and cares for some of
these bugs on clove trees and they may well do the same on mangroves.
The large numbers, always present on the leaves which are woven
together to form the nest, are suggestive of this.
The insects with larvae developing in the surface layers of the mud
do not seem to have been studied in relation to any specializations they
may show. Closely related species occur in mangrove areas and alongside freshwater courses. The same species has been recorded from both
saline and fresh water. Do these differ from one another or not? One
finds two almost contradictory sets of observations.
The first refers to mosquito larvae swimming in saline waters.
These have the anal papillae reduced in comparison with freshwater
forms (see Chapter 3 of Clements, 1963).
On the other hand, it has been shown that larvae of Drosophila
cultured in a saline medium tend to become modified by the enlargement of two papillae at the hind end of the body. Those which can
develop these survive, and their offspring also show the tendency to
possess these enlarged papillae which appear to be concerned with salt
regulation (Waddington, 1959,1960). Are such structures found in soildwelling fly larvae associated with the mangal?
C. Marine animals
When one considers the marine element in the fauna of the mangal
one finds, or expects that one will find, that the animals show some
degree of specialization. All animals living between tide-marks are
adapted to their mode of life, whether they live on rocky, sandy or
muddy shores. Such specializations tend to lie in two directions : they
are related to the ability to live in air as well as in water, i.e. to an
ability to resist desiccation, and also to the ability to adjust to variations
in salinity.
I n the ever-wet the specializations will relate primarily to living in
diluted sea water. I n regions with markedly different wet and dry
seasons they will relate, a t one season to diluted sea water and at the
other to hypersaline conditions of soil water and to a lower humidity
of the air.
Many of the solutions to problems of a varying environment are to
be found in patterns of behaviour, others in modifications in structure
and function of organs, and examples of both may be found in one
species.
Many of the behavioural specializations are centred on activity
concerned with burrowing and the actions and display associated with
WILLIAM MACNAE
these trees they are associated with coccids and other bugs. Way
(1954b) recorded that Oecophylla transplants and cares for some of
these bugs on clove trees and they may well do the same on mangroves.
The large numbers, always present on the leaves which are woven
together to form the nest, are suggestive of this.
The insects with larvae developing in the surface layers of the mud
do not seem to have been studied in relation to any specializations they
may show. Closely related species occur in mangrove areas and alongside freshwater courses. The same species has been recorded from both
saline and fresh water. Do these differ from one another or not? One
finds two almost contradictory sets of observations.
The first refers to mosquito larvae swimming in saline waters.
These have the anal papillae reduced in comparison with freshwater
forms (see Chapter 3 of Clements, 1963).
On the other hand, it has been shown that larvae of Drosophila
cultured in a saline medium tend to become modified by the enlargement of two papillae at the hind end of the body. Those which can
develop these survive, and their offspring also show the tendency to
possess these enlarged papillae which appear to be concerned with salt
regulation (Waddington, 1959,1960). Are such structures found in soildwelling fly larvae associated with the mangal?
C. Marine animals
When one considers the marine element in the fauna of the mangal
one finds, or expects that one will find, that the animals show some
degree of specialization. All animals living between tide-marks are
adapted to their mode of life, whether they live on rocky, sandy or
muddy shores. Such specializations tend to lie in two directions : they
are related to the ability to live in air as well as in water, i.e. to an
ability to resist desiccation, and also to the ability to adjust to variations
in salinity.
I n the ever-wet the specializations will relate primarily to living in
diluted sea water. I n regions with markedly different wet and dry
seasons they will relate, a t one season to diluted sea water and at the
other to hypersaline conditions of soil water and to a lower humidity
of the air.
Many of the solutions to problems of a varying environment are to
be found in patterns of behaviour, others in modifications in structure
and function of organs, and examples of both may be found in one
species.
Many of the behavioural specializations are centred on activity
concerned with burrowing and the actions and display associated with