scholarly journals Aulacaspis yasumatsui Invasion Reduced Cycas micronesica Microstrobilus Size and Pollinator Brood Site Competence

Insects ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 1023
Author(s):  
Thomas E. Marler ◽  
L. Irene Terry
Keyword(s):  
Incubation Period ◽  
Reproductive Effort ◽  
Plant Population ◽  
Male Reproductive Effort

Aulacaspis yasumatsui Takagi invaded Guam in 2003, and the influence on survival and demography of the host Cycas micronesica K.D. Hill population has been well-studied. To more fully understand how A. yasumatsui has threatened the host cycad species, we determined the microstrobilus size and number of pollinators per microstrobilus from 2001 to 2021. The microstrobilus height and diameter were measured directly, and the volume was calculated. Microstrobili were 58 cm in height, 13 cm in diameter, and 4740 cm3 in volume prior to direct A. yasumatsui infestations. Microstrobili decreased in size immediately after direct infestations by A. yasumatsui, and then began to slowly increase in size until 2021. For example, the volume was 24% of pre-invasion volume in 2007, and was 57% of pre-invasion volume in 2021. Microstrobili were harvested; then, the number of pollinator pupae were counted after an incubation period. Pollinator pupae counts per microstrobilus declined to 66% of pre-invasion levels by 2007 and have remained similarly constrained through 2021. Our results revealed that A. yasumatsui damage to the host C. micronesica population is not limited to attrition of the extant plant population, but also includes a loss in male reproductive effort and the risk of coextinction of the insular pollinator.

scholarly journals Give ‘til it hurts: trade-offs between immunity and male reproductive effort in the decorated cricket,Gryllodes sigillatus

2010 ◽  
Vol 23 (4) ◽  
pp. 829-839 ◽  
Author(s):  
S. N. GERSHMAN ◽  
C. A. BARNETT ◽  
A. M. PETTINGER ◽  
C. B. WEDDLE ◽  
J. HUNT ◽  
...  
Keyword(s):  
Reproductive Effort ◽  
Trade Offs ◽  
Gryllodes Sigillatus ◽  
Male Reproductive Effort ◽  
Decorated Cricket

scholarly journals The timing of male reproductive effort relative to female ovulation in a capital breeder

2008 ◽  
Vol 77 (3) ◽  
pp. 469-477 ◽  
Author(s):  
Atle Mysterud ◽  
Christophe Bonenfant ◽  
Leif Egil Loe ◽  
Rolf Langvatn ◽  
Nigel G. Yoccoz ◽  
...  
Keyword(s):  
Reproductive Effort ◽  
Capital Breeder ◽  
Male Reproductive Effort

scholarly journals Interpopulation differences in male reproductive effort drive the population dynamics of a host exposed to an emerging fungal pathogen

2021 ◽  
Author(s):  
Andrés Valenzuela‐Sánchez ◽  
Claudio Azat ◽  
Andrew A. Cunningham ◽  
Soledad Delgado ◽  
Leonardo D. Bacigalupe ◽  
...  
Keyword(s):  
Population Dynamics ◽  
Fungal Pathogen ◽  
Reproductive Effort ◽  
Male Reproductive Effort

scholarly journals Tandem Androgenic and Psychological Shifts in Male Reproductive Effort Following a Manipulated “Win” or “Loss” in a Sporting Competition

Human Nature ◽  
2018 ◽  
Vol 29 (3) ◽  
pp. 283-310 ◽  
Author(s):  
Daniel P. Longman ◽  
Michele K. Surbey ◽  
Jay T. Stock ◽  
Jonathan C. K. Wells
Keyword(s):  
Reproductive Effort ◽  
Male Reproductive Effort

scholarly journals Does male reproductive effort increase with age? Courtship in fiddler crabs

2013 ◽  
Vol 9 (2) ◽  
pp. 20121078 ◽  
Author(s):  
Catherine L. Hayes ◽  
Isobel Booksmythe ◽  
Michael D. Jennions ◽  
Patricia R. Y. Backwell
Keyword(s):  
Egg Size ◽  
Reproductive Effort ◽  
Female Preference ◽  
Age Dependence ◽  
Experimental Protocol ◽  
Fiddler Crabs ◽  
Age Dependent ◽  
Uca Annulipes ◽  
Female Presence ◽  
Male Reproductive Effort

Theory suggests that reproductive effort generally increases with age, but life-history models indicate that other outcomes are possible. Empirical data are needed to quantify variation in actual age-dependence. Data are readily attainable for females (e.g. clutch per egg size), but not for males (e.g. courtship effort). To quantify male effort one must: (i) experimentally control for potential age-dependent changes in female presence; and, crucially, (ii) distinguish between the likelihood of courtship being initiated, the display rate, and the total time invested in courting before stopping (‘courtship persistence’). We provide a simple experimental protocol, suitable for many taxa, to illustrate how to obtain this information. We studied courtship waving by male fiddler crabs, Uca annulipes . Given indeterminate growth, body size is correlated with age. Larger males were more likely to wave at females and waved more persistently. They did not, however, have a higher courtship rate (waves per second). A known female preference for males with higher display rates explains why, once waving is initiated, all males display at the same rate.

scholarly journals The influence of male age and simulated pathogenic infection on producing a dishonest sexual signal

2012 ◽  
Vol 279 (1748) ◽  
pp. 4740-4746 ◽  
Author(s):  
Emily K. Copeland ◽  
Kenneth M. Fedorka
Keyword(s):  
Reproductive Effort ◽  
Reproductive Value ◽  
Female Fitness ◽  
Sexual Signal ◽  
Terminal Investment ◽  
Male Age ◽  
Residual Reproductive Value ◽  
Male Reproductive Effort ◽  
Allonemobius Socius ◽  
Pathogenic Infection

In recent years, studies have shown that reproductive effort decelerates in response to pathogenic infection. If infection substantially reduces a host's residual reproductive value (RRV), however, then an acceleration of effort may instead occur (e.g. terminal investment). Reproductive acceleration would theoretically allow hosts to maintain or exaggerate their sexual signal upon infection. This would create a deceptive message from the perspective of the chooser, who may unwittingly copulate with an infected mate to their detriment. Using the cricket Allonemobius socius , we assessed the potential for reduced RRV to accelerate male reproductive effort and create a dishonest signal. RRV was manipulated through male age and simulated pathogenic insult. Reproductive effort was measured as calling song energetics, mating success, latency to mate and nuptial gift size. We show that males adopted either an accelerated or decelerated reproductive strategy upon infection, and that this decision was probably mediated by RRV. Moreover, males who accelerated their effort produced a dishonest signal by increasing their song energetics while providing fewer paternal resources (i.e. smaller gifts). Our study is one of the few to document the existence of dishonest signals and relate dishonesty to a potential reduction in female fitness, underscoring the conflict inherent in sexual reproduction.

scholarly journals Hermaphrodites and parasitism: size-specific female reproduction drives infection by an ephemeral parasitic castrator

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Caitlin R. Fong ◽  
Armand M. Kuris ◽  
Ryan F. Hechinger
Keyword(s):  
Reproductive Effort ◽  
Reproductive Function ◽  
Simultaneous Hermaphrodite ◽  
Female Reproduction ◽  
Female Function ◽  
Males And Females ◽  
Selection For ◽  
Parasitic Castrator ◽  
Male Reproductive Effort ◽  
The Relationship

AbstractSex can influence patterns of parasitism because males and females can differ in encounter with, and susceptibility to, parasites. We investigate an isopod parasite (Hemioniscus balani) that consumes ovarian fluid, blocking female function of its barnacle host, a simultaneous hermaphrodite. As a hermaphrodite, sex is fluid, and individuals may allocate energy differentially to male versus female reproduction. We predicted the relationship between barnacle size and female reproductive function influences the distribution of parasites within barnacle populations. We surveyed 12 populations spanning ~400 km of coastline of southern California and found intermediate-sized barnacles where most likely to be actively functioning as females. While it is unclear why larger individuals are less likely to be actively reproducing as females, we suggest this reduced likelihood is driven by increased investment in male reproductive effort at larger sizes. The female function-size relationship was mirrored by the relationship between size and parasitism. We suggest parasitism by Hemioniscus balani imposes a cost to female function, reinforcing the lack of investment in female function by the largest individuals. Within the subset of suitable (=female) hosts, infection probability increased with size. Hence, the distribution of female function, combined with selection for larger hosts, primarily dictated patterns of infection.

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