Data for Sex-specific consequences of experimentally induced host shift on morphology and fluctuating asymmetry in seed beetle: experimental evolution approach

Subject:We performed reciprocal transplant experiment in eight replicated seed beetle (Acanthoscelides obtectus) populations adapted to bean - ancestral host and chickpea -suboptimal host. Using methods of geometric morphometrics we assessed the effects of the short- and long-term host shift on size and shape variation of beetles of both sexes. 

Material and methods:For this experiment, we established 4 experimental groups (each group in 4 replicas; Figure 1): (i) Pp - beetles from P selection regime developed on beans for one generation with individuals selected on common bean for 145 generations; (ii) Cc - beetles from C selection regime developed on chickpea for one generation with individuals selected on chickpea for 136 generations; (iii) Pc - beetles from P selection regime developed on chickpea for one generation; and (iv) Cp - beetles from C selection regime developed on beans for one generation. Immediately upon emergence, we collected around 30 females and males per replica per experimental group, in total 500 females and 484 males.  Beetles were collected in 1.5 ml Eppendorf tubes and stored on -20° C. Adults, one by one, were set on plasticine mold glued to a microscope plate and photographed with Nikon Digital Sight Fi2 Camera attached to Nikon SMZ800 against a scale bar 10mm on ventral side.

Analysis:To characterize the shape of beetle's body, we applied the methods of geometric morphometrics, which use the relative positions of set a landmarks to quantify morphological variation. We selected configurations of 22 landmarks of objects (12 landmarks for the thorax and 10 landmarks for abdomen. The landmarks were digitized by one person in TpsDig2 software.

Sample type: Landmark coordinates.

Platform:tps dig2, MorphoJ

Instrument control:NA

Data acquisition:tps dig2, MorphoJ

Data processing:MorphoJ, R software

Data analysis:Digitizing samples of seed beetles photpographed under the binocular.

Statistics: Raw data are presented, not subjected to the statistical analyses.

Data presentation: Presented data are raw data of 22 landmarks of objects (12 landmarks for the thorax and 10 landmarks for abdomen) in 4 populations of Acanthoscelides obtectus adapted on either bean or chickpea plant hosts and are presented as landmark coordinates. Data are presented in 1 .csv file.

Highlight:Switching host plants can cause morphological changes in insects, with sex-specific effects. We studied bean-adapted and chickpea-adapted seed beetles (Acanthoscelides obtectus) using geometric morphometrics. Female beetles showed greater plasticity in body size and abdomen shape during short-term host shifts, suggesting their importance in adapting to new hosts. Males adapted to beans exhibited the least fluctuating asymmetry, indicating stable development due to sexual selection. Beetles stabilized their development upon returning to the ancestral host, even after generations on a suboptimal host.

Abbreviations:NA