Figure 1.
(A) Topography of the habitat (Sopeira, Spanish Pyrenees), (B) flowering male plant, (C) flowering female plant with a visiting ant (Lasius), (D) male flowers with a visiting ant (Lasius), (E) female plant with two fruits, one at a crevice in the cliff wall (self sowing), (F) seed with elaiosome coating, (G) vial containing seeds in situ–for cafeteria experiments (Experiment I, see Materials and Methods), (H) ant removing a seed (Experiment I), and (I) tuber with old leaf scars marked with a red coloration, each dot corresponds to one year, and a ruler shows its size in mm.
Figure 2.
Seed–dispersal modes of Borderea chouardii.
Dispersal by gravity (G) is assumed to take place within a circular section of 45° below a mother and >10 cm away from the mother. Dispersal by ants (A) takes place in all directions and >10 cm away from the mother, and self–sowing (S) is restricted to a circular area of a radius of 10 cm and the mother plant as its center.
Table 1.
Flower visitation of Borderea chouardii.
Figure 3.
Reproductive success of Borderea chouardii over 17 years.
Reproductive success was estimated as fruit set of individual plants (blue dots; percentage of fruits to flowers) and seed set (red squares; percentage of seeds to ovules).
Figure 4.
Removal of different kinds of seed items of Borderea chouardii from in situ cafeteria experiments.
Categories are seeds with elaiosome (2008, 2009, 2011), seeds without elaiosome (2009), individual elaiosomes (2009) and entire open fruits containing 6 seeds (2010).
Figure 5.
Frequency of seed removal of four plant species in natural nests of the ant Pheidole pallidula.
Bch = Borderea chouardii, Bp = Borderea pyrenaica, Se = Sarcocapnos enneaphylla, and Sa = Silene acaulis.