Frugivory, Seed Predation, and Insect-Vertebrate Interactions

Sallabanks, Rex; Courtney, Steven P.

doi:10.1146/annurev.en.37.010192.002113

Cited by 147 publications

(98 citation statements)

References 94 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Third, are chemical secretions from the female moth necessary to disrupt ovule development or trigger abscission? Insect secretions, particularly the effects of plant piercing/sucking gall insects, have been shown to affect plant metabolism and alter hormonal balance enough to cause floral abscission (reviewed in Hori 1992; Sallabanks and Courtney 1992). Last, does the presence of moth eggs disrupt ovule development?…”

Section: Introductionmentioning

confidence: 99%

Effect of pollinator-inflicted ovule damage on floral abscission in the yucca-yucca moth mutualism: the role of mechanical and chemical factors

Marr

Pellmyr

2003

Oecologia

View full text Add to dashboard Cite

The long-term persistence of obligate mutualisms (over 40 Mya in both fig/fig wasps and yucca/yucca moths) raises the question of how one species limits exploitation by the other species, even though there is selection pressure on individuals to maximize fitness. In the case of yuccas, moths serve as the plant's only pollinator, but eggs laid by the moths before pollination hatch into larvae that consume seeds. Previous studies have shown that flowers with high egg loads are more likely to abscise. This suggests that yucca flowers can select against moths that lay many eggs per flower through selective abscission of flowers; however, it is not known how yucca moths trigger floral abscission. We tested how the moth Tegeticula yuccasella triggers floral abscission during oviposition in Yucca filamentosa by examining the effects of ovipositor insertion and egg laying on ovule viability and floral abscission. Eggs are not laid at the site of ovipositor insertion: we used this separation to test whether wounded ovules were more closely associated with the ovipositor site or an egg's location. Using a tetrazolium stain to detect injured ovules, we determined whether the number of ovipositions affected the number of wounded ovules in naturally pollinated flowers. Two wounding experiments were used to test the effect of mechanical damage on the probability of floral abscission. The types of wounds in these experiments mimicked two types of oviposition-superficial oviposition in the ovary wall and oviposition into the locular cavity-that have been observed in species of Tegeticula. The effect of moth eggs on ovule viability was experimentally tested by culturing ovules in vitro, placing moth eggs on the ovules, and measuring changes in ovule viability with a tetrazolium stain. We found that ovules were physically wounded during natural oviposition. Ovules showed a visible wounding response in moth-pollinated flowers collected 7-12 h after oviposition. Exact location of wounded ovules relative to eggs and oviposition scars, as well as results from the artificial wounding experiments, showed that the moth ovipositor inflicts mechanical damage on the ovules. Significantly higher abscission rates were observed in artificially wounded flowers in which only 4-8% of the ovules were injured. Eggs did not affect ovule viability as measured by the tetrazolium stain. These results suggest that physical damage to ovules caused by ovipositing is sufficient to explain selective fruit abscission. Whether injury as a mechanism of selective abscission in yuccas is novel or a preadaptation will require further study.

show abstract

Section: Introductionmentioning

confidence: 99%

Effect of pollinator-inflicted ovule damage on floral abscission in the yucca-yucca moth mutualism: the role of mechanical and chemical factors

Marr

Pellmyr

2003

Oecologia

View full text Add to dashboard Cite

show abstract

“…The possible influence of infestation on fruit attractiveness to dispersing frugivores suggests that plant chemical defenses, fruit nutrient constitution, vertebrate frugivore nutrition and foraging behavior, and population dynamics of fruitinfesting organisms could interact to influence fruit seed dispersal (Scott and Black 1981;Herrera 1982;Manzur and Courtney 1984;Redford et al 1984;Safriel 1989, 1990;Sallabanks and Courtney 1992;Valburg 1992a,b).…”

Section: Introductionmentioning

confidence: 99%

Effects of weevil larvae on acorn use by blue jays

1997

View full text Add to dashboard Cite

Blue jays (Cyanocitta cristata L.) are important consumers and dispersers of the nuts of oaks and other fagaceous trees in eastern North America. Acorns compose much of the jay diet, especially during the autumn when jays may consume or cache a significant portion of an acorn crop. However, jays do not appear to possess physiological adaptations for countering the protein-binding properties of secondary compounds (tannins) found in acorns. We offered captive blue jays a mixture of infested and uninfested pin oak (Quercus palustris Muenchh.) acorns to see if the birds would selectively consume nuts containing weevil larvae (Coleoptera: Curculionidae) as a protein supplement to a high-tannin, all-acorn diet. Acorns were X-rayed to determine infestation status and then offered to individual jays in an outdoor aviary. Jays handled, opened, and consumed uninfested nuts significantly more often than infested nuts, and use of infested nuts did not increase during continued exposure to a high-tannin diet.

show abstract

“…In other situations, however, the costs may be so great that it is impossible to understand the evolution and current function of certain traits except in light of this exploitation. For example, a variety of¯oral traits (Inouye 1983;Prys-Jones and Willmer 1992) and fruit traits (Cipollini and Stiles 1992;Sallabanks and Courtney 1992) have been interpreted as adaptations to exclude costly nonmutualistic species such as nectar-robbers and fruit predators. Furthermore, attempts to interpret mutualisms in terms of the costs mutualists are apparently willing to pay to receive service (e.g., Janzen 1979;Addicott 1986;NoeÈ and Hammerstein 1994) may have to be signi®cantly altered if much of the observed costs are actually attributable to non-mutualistic organisms.…”

Section: Discussionmentioning

confidence: 99%

Costs of two non-mutualistic species in a yucca/yucca moth mutualism

Bronstein

Ziv

1997

Oecologia

View full text Add to dashboard Cite

Mutualisms often involve significant costs for participants. Costs are inflicted by mutualists themselves, as well as by associated, non-mutualistic species. These costs are rarely quantified, however, particularly the ones extrinsic to the pairwise interaction. We compare costs inflicted by an obligate mutualist pollinator and two common exploiters of an Arizona yucca over a 2-year period. The magnitude of seed damage from seed and fruit-feeding beetle larvae (Carpophilus longus, Nitidulidae) was similar to damage from the seed-eating larvae of Yucca schottii's pollinator moth Tegeticula yuccasella (Prodoxidae), averaging about 15 seeds destroyed per fruit in each case. The two seed predators usually fed within the same fruits, although rarely side by side. In contrast, the presence of fruit-galling moth larvae (Prodoxusy-inversus, Prodoxidae) appeared to benefit the yucca: individual Tegeticula destroyed only half as many seeds in galled fruits as they did in ungalled fruits. We discuss three general implications of these results. Firstly, the costs of non-mutualists to the two mutualistic partners are not necessarily parallel. Secondly, measurable costs of non-mutualists do not necessarily translate into an impact on the success of the mutualism itself, because they may be incurred after mutualistic activities take place. Finally, the costs of mutualists to each other can differ substantially depending on the presence or absence of non-mutualistic species.

show abstract

Frugivory, Seed Predation, and Insect-Vertebrate Interactions

Cited by 147 publications

References 94 publications

Effect of pollinator-inflicted ovule damage on floral abscission in the yucca-yucca moth mutualism: the role of mechanical and chemical factors

Effect of pollinator-inflicted ovule damage on floral abscission in the yucca-yucca moth mutualism: the role of mechanical and chemical factors

Effects of weevil larvae on acorn use by blue jays

Costs of two non-mutualistic species in a yucca/yucca moth mutualism

Contact Info

Product

Resources

About