verde pastures, these species remain leafless for a
month or two, but in the forest they leaf out within a
few weeks. In the San Luis valley, deciduous species
are more common and may remain leafless for sev-
eral months during the dry season.
Understory shrubs. The seasonal pattern of leaf flush-
ing in understory shrubs is less conspicuous than in
trees; however, a slight increase in leaf flushing oc-
curs during the dry season (Koptur et al. 1988).
3.2.5. Studies of Guilds
Hummingbird flowers. Shrubs and treelets of the un-
derstory with flowers adapted for hummingbird pol-
lination show little seasonal pattern in flowering
(Koptur et al. 1988). In a study of all hummingbird-
pollinated plants occurring in light gaps and in the
understory of the cloud forest, flowering was uniform
through the year, with a small increase in the num-
ber of species flowering during October through
December (Linhart et al. 1987). At a drier site in pre-
montane wet forest below the Monteverde commu-
nity, more hummingbird flowers bloomed during the
dry season, although most species had flowering pat-
terns that extended over several months (Feinsinger
1978).
Inga. Koptur (1983; see Koptur, "Breeding Systems,"
p. 85) studied the reproductive biology of seven
Inga species (Fabaceae) in Monteverde. Flowering
was distributed throughout the year, but more spe-
cies flowered during late wet season to early dry
season (September-December) when hawkmoths
(Sphingidae) and perching moths (e.g., Geometridae,
Noctuidae) were abundant. Few species flowered
from late dry season to early wet season. Several spe-
cies tended to flower twice per year or displayed ex-
tended flowering with double peaks. In these cases,
the separate flowering episodes resulted mostly from
flowering by different individuals i.e., some individu-
als within populations (e.g., I. longispica) flowered at
different times of year from others. The peaks roughly
coincided with the two peaks in rainfall (May—June
and September-October). For moth-pollinated flow-
ers in general at Monteverde, a peak in flowering
occurs in the early wet season (May—June; W. Haber,
unpubl. data).
The fruiting phenologies of the Inga species over-
lapped even more than the flowering periods. Six of
the seven species produced mature fruit during the
late dry season and early wet season. Because Inga
seeds are not protected against desiccation, seed ma-
turation at the beginning of the wet season could beviewed as an adaptation for seedling establishment
during favorable growing conditions.Lauraceae. A phenological study of 23 species of
Lauraceae at Monteverde showed that the distribution
of the flowering periods through the year was indistin-
guishable from a random pattern (Wheelwright 1985,
1986, 1988, unpubl. data). Small peaks that occurred
during September-October and March-May were not
significantly different from a uniform distribution.
Because the Lauraceae are pollinated by a wide vari-
ety of generalist insects (e.g., Hymenoptera, Diptera,
Lepidoptera), the timing of flowering need not con-
form to the life history of a particular pollinator.
As with the Inga species, fruiting in the Lauraceae
is significantly aggregated, with a peak of 13 species
in fruit during the early wet season and a low period
of three species in fruit during the early dry season.
Seeds of Lauraceae cannot withstand desiccation and
germinate soon after dispersal (Wheelwright 1985).
The fruits are eaten and the seeds dispersed by large
birds, such as Emerald Toucanets, Resplendent Quet-
zals, and Three-wattled Bellbirds (the latter two species
are seasonal, intra-tropical migrants). Little evidence
exists for the hypothesis that fruiting phenologies are
staggered uniformly through the year to avoid compe-
tition for seed dispersers (Wheelwright 1985). Rather,
the timing of fruiting in the Lauraceae is constrained
by the germination requirements of seeds and perhaps
also by the life histories of seed dispersers, such as the
importance of fruit availability during the nesting pe-
riod of quetzals (Wheelwright 1983). The timing of
flowering, on the other hand, may more likely be in-
fluenced by competition for pollinators (see Wheel-
wright, "Sex Ratios," pp. 87-88).Hawkmoth flowers. Unlike Inga species, other plants
adapted for pollination by hawkmoths show a distinct
flowering peak from April through June, at the start
of the rainy season. High numbers continue through
the rest of the wet season into October. This flower-
ing pattern parallels the changes in seasonal abundance
of hawkmoths, whose numbers build up through the
wet season and decrease rapidly during the dry sea-
son (Haber 1983, 1984, Haber and Frankie 1988, W.
Haber, unpubl. data).3.3. Population BiologyWith the exception of the areas of pollination and seed
dispersal, little research on the population biology of
plants has been done at Monteverde. The detailed
demographic studies of Ocotea tenera are an excep-
tion (Gibson and Wheelwright 1995,1996; see Wheel-66 Plants and Vegetation