Size dependent predatory pressure in the Japanese horned beetle,Allomyrina dichotoma L. (Coleoptera; Scarabaeidae)

Setsuda, Kenichi; Tsuchida, Koji; Watanabe, Hiroyuki; Kakei, Yoshichika; Yamada, Yoshiki

doi:10.1007/bf02769300

Cited by 21 publications

(18 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Allomyrina dichotoma (= Trypoxylus dichotomus ) is a horned beetle that has been the subject of interest recently, from behavioural ecologists interested in subjects including contests between males, the fitness consequences of size and horn length, and the relationship between size and predation risk ( Siva-Jothy, 1987;Setsuda et al , 1999;Hongo, 2003, in press;Karino et al , 2004Karino et al , , 2005Plaistow et al , 2005 ). A log -log scatterplot of horn length against body size [ Fig.…”

Section: Worked Example 2: Horn Allometry In Allomyrina Dichotomamentioning

confidence: 99%

On the analysis of non‐linear allometries

Knell

2009

Ecological Entomology

108

View full text Add to dashboard Cite

. 1. Non-linear allometries are those where a log -log scatterplot of trait size against body size deviates from simple linearity. These are found in many insects, including the horns of beetles, the forceps of earwigs, and the heads of certain castes of ant.2. Non-linear allometries are often associated with polyphenism that is itself related to behaviour: for example, the alternative mating tactics displayed by many species of beetle are widely associated with dimorphisms in horn size.3. This paper critically reviews the current techniques used to analyse these datasets. 4. Recommendations include the use of scatterplots and assessment of the goodness of fit of simple linear models as an initial screen for non-linear allometry. The use of recently developed algorithms for 'segmented' regression to analyse continuous allometric relationships, and a pragmatic approach to the analysis of discontinuous relationships that recognises that there is no simple way to distinguish between morphs in some cases, and that all of the proposed methods for doing so have some drawbacks.5. Worked examples of the analysis of two sets of data from animals that have been the subject of controversy regarding the nature of their allometric relationships are given: further worked examples are provided as online Supporting Information .Key words . Allometry , Allomyrina , analysis , dimorphism , non-linear allometry , polyphenism , switchpoint , Onthophagus . the detection and further analysis of non-linear allometries, with particular emphasis on dimorphic allometries, and makes recommendations for the best way to analyse a variety of different sorts of such non-linear allometric relationships. The use of these analyses is illustrated by two worked examples, and three further worked examples are provided as online Supporting Information . Figure 1 shows scatterplots of non-linear allometries from three insect species. It is obvious from a glance at this figure that there is substantial variation in these relationships, and the form of the relationship is an important consideration in deciding which analysis to use. The simplest and most important division is into what can be called continuous and discontinuous allometries. Continuous allometries are those where the allometric relationship can be regarded as a single, albeit not necessarily straight, line. These allometries can include simple curved relationships ( Fig. 1a ), ones with a switchpoint where the slope of the relationship changes abruptly [as is claimed, for example, for the horned beetle Onthophagus binodis ( Cook, 1987 ; see also Supporting Information Example 1) and for the fig wasp Sycoscapter australis ( Bean & Cook, 2001 )] and also those that show sigmoid patterns such as Onthophagus taurus ( Fig. 1b ). Discontinuous allometries are those that are divided into two (or more) discontinuous groups, which may be more or less separated from each other and which are not adequately modelled by a continuous line. Such discontinuous allometries are described from ma...

show abstract

Section: Worked Example 2: Horn Allometry In Allomyrina Dichotomamentioning

confidence: 99%

On the analysis of non‐linear allometries

Knell

2009

Ecological Entomology

108

View full text Add to dashboard Cite

show abstract

“…Allomyrina dichotoma Linnaeus (Scarabaeidae)] suffer a slightly higher predatory pressure (Setsuda et al, 1999). Additionally, the behaviour of the major and minor morphs is known to differ in a number of beetle species (e.g.…”

Section: Alternative Explanationsmentioning

confidence: 99%

Seasonal constraints on the mandible allometry of Lucanus cervus (Coleoptera: Lucanidae)

Hardersen¹,

Macagno²,

Sacchi³

et al. 2011

Eur. J. Entomol.

View full text Add to dashboard Cite

Abstract. In insects, allometries of exaggerated traits such as horns or mandibles are often considered species specific and constant during a season. However, given that constraints imposed by the advancing season affect the developmental processes of organisms, these allometries may not be fixed, and the switch point between morphs may vary between populations and within populations during a season. The hypothesis of such a seasonal variation in exaggerated traits was tested using the dimorphic males of the beetle Lucanus cervus. The remains of specimens killed by predators were collected along forest tracks from mid May to late August 2008 in a protected lowland forest in northern Italy. The largest beetles were collected in mid May and average size thereafter decreased. Males collected early in the season mostly had large mandibles (i.e. they belonged to the major morph). In contrast, late in the season the probability of finding males with large mandibles was very low. The threshold body size determining morph expression also shifted during the season. Early in the season, the threshold pronotum width for a 50% chance of developing into the major morph was 1.74 cm, whereas later in the season it was 1.90 cm. This shift in the threshold body size was interpreted as the effect of phenotypic plasticity in a population exposed to constraints imposed by the advancing season.

show abstract

“…In addition, we neither observed Brown Hawk Owls nor heard its calls during the study period, which was its breeding season. Setsuda et al (1999) suggested the possibility that Japanese horned beetles were preyed upon by two crow species Corvus macrorhynchos and C. corone. In our study, the dead beetles were mostly found at sites wherein they did not occur during daytime.…”

Section: Field Observations Of Predation By the Ural Owl Strix Uralensismentioning

confidence: 99%

Field Observations of Predation by the Ural Owl Strix uralensis upon the Japanese Horned Beetle Trypoxylus dichotomus septentrionalis

Hongo¹,

Kaneda²

2009

J. Yamashina Inst. Ornithol.

View full text Add to dashboard Cite

Abstract. Generally, it has been considered that the Ural Owl Strix uralensis feeds mainly on small birds, amphibians and small mammals such as voles, and only rarely on insects. However, we found that the Ural Owl often preys upon the Japanese horned beetle Trypoxylus dichotomus septentrionalis, which has never before been reported as an insect prey species for the Ural Owl. We here demonstrate that Ural Owls at the present study site frequently prey upon Japanese horned beetles for a limited period during summer. Details of the predatory behavior of Ural Owls upon beetles are also given.

show abstract

Size dependent predatory pressure in the Japanese horned beetle,Allomyrina dichotoma L. (Coleoptera; Scarabaeidae)

Cited by 21 publications

References 8 publications

On the analysis of non‐linear allometries

On the analysis of non‐linear allometries

Seasonal constraints on the mandible allometry of Lucanus cervus (Coleoptera: Lucanidae)

Field Observations of Predation by the Ural Owl Strix uralensis upon the Japanese Horned Beetle Trypoxylus dichotomus septentrionalis

Contact Info

Product

Resources

About