|
|
Implications
Two main implications can be deduced from Antipredator defense as a limited
resource performed by Dr. Cocroft. The implications can be drawn from the results
and discussion sections of the report written by Dr. Crocroft.
The first implication comes from the result showing that maternal care of
U. crassicornis is not equally distributed among the nymphs. This begs the
question: How is maternal care distributed then if it is not equal The
conclusion that maternal care is distributed unequally among the nymphs implies
that there is competition among the offspring for defense against predators
from the mother. Although the study showed that sibling rivalry for maternal
protection is not found in nymph signaling for maternal care, it is possible
that the nymphs attempt to position themselves close to the mother. Nymphs
were not as likely to be removed by a wasp if they were located on the proximal
portion of the branch, which is where the mother resided when not protecting
her offspring from a predator. These results imply that nymphs would compete
for this position since it allows for a higher survival rate.
The second implication is that nymphs would also compete for location on
the branch independent of the mother's location. Nymphs located on the edges
of the aggregation were 23 time more likely to be removed by a predator than
offspring located in the center of the aggregation. This is known as the
edge effect. This result implies that nymphs will compete for central
locations on the branch. Interference competition (i.e., shoving) was not
observed although exploitation competition is possible. If certain nymphs
occupy and remain in a central position on the branch, other nymphs are forced
to the edges.
It should also be noted that two implications cannot be deduced from the
experiment, as it shows these implications to be untrue. Nymphs signaled
in unison for maternal care, with no nymph signaling louder or longer than
any other nymph, although this type of competition for maternal care would
seem possible. Signaling of the nymphs for maternal care was cooperative
and the mother did not respond to any nymph or nymphs unequally. The mother
distributed her protection equally throughout the entire aggregation along
the length of the branch.
Main Points:
Location in relation to the mother is possibly competitive
Location independent of the mother is possibly competitive, but only
exploitation competition
Signaling is not competitive for maternal care, it is cooperative and the
mother distributes protection along the aggregation equally.
|