Biology Reference
In-Depth Information
(a)
(b)
12
10
10
8
8
Present
6
Absent
6
4
4
2
2
0
0
-0.06
-0.4
-0.2
0
0.2
0.4
0.6
Primary male
Primary female
Mean subordinate-nestling relatedness
Fig. 12.11
Cooperation and kin discrimination in the Seychelles warbler. (a) The
provisioning rate of female subordinates (filled circles and solid line) showed a positive
relationship with relatedness to the nestlings being fed, whereas the provisioning rate of
male subordinates (empty circles and dashed line) did not. (b) The provisioning rate of
female subordinates was significantly higher when the dominant female at the nest was
the dominant female at the time of their birth, but showed no relationship with the
identity of the dominant male. From Richardson
et al
. (2003). Photo © Martijn Hammers.
butterfly larvae, which ant workers carry into their nests and then feed, thanks to the
butterflies ability to mimic the chemical scents and sounds of ants (Barbero
et al
., 2009).
Manipulation also occurs within a species. For example, some female birds lay eggs
in the nests of conspecifics, thus avoiding the costs of incubation and parental care
(Yom-Tov, 1980). Female starlings,
Sturnus vulgaris
, who 'dump' eggs in other female's
nests first remove a host egg before laying their own. They then deposit the host egg on
the ground nearby. It was at first thought that these eggs which appeared on the ground
were laid by females who were unable to get back to their nests in time to lay normally!
Then, when eggs were marked in nests as they were laid, it was found that the eggs
Individuals may
be tricked into
helping others
