Wing asymmetry of a butterfly community: is altitude a source of stress?

Abstract

We present a novel analysis of fluctuating asymmetry (FA) for butterfly wings at the community-level, along an altitudinal gradient. FA is an important biomonitoring tool that detects deviations of perfect symmetry in bilateral characters, assuming that genetic and/or environmental factors can be a source of stress. This study evaluated the effects of increased altitude on the symmetry of butterfly wings, testing the hypothesis that FA should increase with increased elevation in a tropical mountain. Butterflies were sampled along an altitudinal gradient of 800 to 1.400 m and forewings were detached, scanned and evaluated for symmetry. Length, width and area of the right and left forewings were measured as surrogates for FA and then combined into an index taking into account the variability of wing sizes of the whole butterfly community. We observed true patterns of FA in the length, width and area of the wings, and wing FA area increased with increased altitude. This study pioneered the analysis of FA for a community of butterflies and FA was efficient to detect developmental instability indicated by imperfections in butterfly wings.

Is elevation a strong environmental filter? Combining taxonomy, functional traits and phylogeny of butterflies in a tropical mountain

“…We measured flying traits of a total of 342 butterflies, belonging to 30 species (Figure SI‐1) of the families Nymphalidae ( S = 15, N = 158), Hesperiidae ( S = 6, N = 88), Pieridae ( S = 5, N = 70), Lycaenidae ( S = 2, N = 18) and Papilionidae ( S = 2, N = 8). Because in a previous study this same butterfly community exhibited wing asymmetry (Henriques & Cornelissen, 2019), we opted to take measurements for wing traits for both the right and left forewings, taking the average of both wings as trait descriptors. We selected seven functional traits that could be measured for the entire community, regardless of species‐specific characteristics: wing length, wing width, wing area, thorax volume, wing:thorax ratio (WTR) length , WTR width and WTR area .…”

Signatures of increasing environmental stress in bumblebee wings over the past century: Insights from museum specimens

“…Despite the consistent trend across species over time, we note that unexplained variance in FA remains. This could be due to differences in local habitat or microclimate (Henriques & Cornelissen, 2019; Kark, 2001; Schmeller et al, 2011) or other stressful conditions, which could interact in non‐additive ways (Zaragoza‐Trello et al, 2021). Alternatively, variance in FA could also be influenced by the positioning of wings on museum specimens.…”

Elevational environmental stress modulating species cohabitation in nests of a social insect

“…In conclusion, we showed that permanent harshness in the form of elevational‐driven stress (Lobregat et al ., 2018; Henriques & Cornelissen, 2019), favours macro‐symbioses within N. coxipoensis nests. Moreover, we provide strong evidence that, in addition to small‐scale abiotic factors (see Cristaldo et al ., 2012), large‐scale ones may also play a definitive role in termitaria invasion by termitophiles.…”

“…High‐montane systems provide a natural experiment for the effects of permanent harshness and SGH, because elevation increments show a strong correlation with environmental stress increments. Moreover, providing that such gradients are bound to determine species interactions (Callaway et al ., 2002; Henriques & Cornelissen, 2019) these gradients may ultimately drive termitaria cohabitation. The Espinhaço Mountain Range in Brazil seems particularly suitable to test such a hypothesis (Silveira et al ., 2019).…”