Best Practices for Bioacoustic Analysis of Wood Frog (Rana sylvatica) Advertisement Calls Over a Suburbanization Gradient

Identifying how species respond to an anthropogenic change in their environment is crucial to understanding species persistence and best conservation practices. Wood frogs (Rana sylvatica) can be found throughout all of North America in both human-disturbed and remote habitats, and they are therefore an excellent species to use to test the impacts of environmental change on their behavior and physiology. Wood frog mating activity includes male congregation and auditory chorusing behavior (i.e., advertisement calls). I explored bioacoustics methods for analyzing these wood frog advertisement calls across a suburbanization gradient to determine if and how suburbanization affects the pitch, duration, and number of advertisement calls. I present best practices for measuring individual advertisement calls in the bioacoustics analysis program Raven, and I explain my hypotheses and present preliminary results.https://orb.binghamton.edu/research_days_posters_2023/1023/thumbnail.jp

Photography-based taxonomy is inadequate, unnecessary, and potentially harmful for biological sciences

The question whether taxonomic descriptions naming new animal species without type specimen(s) deposited in collections should be accepted for publication by scientific journals and allowed by the Code has already been discussed in Zootaxa (Dubois & Nemésio 2007; Donegan 2008, 2009; Nemésio 2009a–b; Dubois 2009; Gentile & Snell 2009; Minelli 2009; Cianferoni & Bartolozzi 2016; Amorim et al. 2016). This question was again raised in a letter supported by 35 signatories published in the journal Nature (Pape et al. 2016) on 15 September 2016. On 25 September 2016, the following rebuttal (strictly limited to 300 words as per the editorial rules of Nature) was submitted to Nature, which on 18 October 2016 refused to publish it. As we think this problem is a very important one for zoological taxonomy, this text is published here exactly as submitted to Nature, followed by the list of the 493 taxonomists and collection-based researchers who signed it in the short time span from 20 September to 6 October 2016

Laboratory-reared offspring

This file contains body size, date of metamorphosis, and parent morphology of all wood frog larvae that were reared in the laboratory

Field-reared offspring

This file contains the Gosner stages, sizes, and parent sizes of the wood frog larvae that were reared in field enclosures

Data from: Fitness costs of mating with preferred females in a scramble mating system

Little is known about the operation of male mate choice in systems with perceived high costs to male choosiness. Scramble mating systems are one type of system in which male choice is often considered too costly to be selected. However, in many scramble mating systems, there are also potentially high rewards of male choosiness, as females vary dramatically in reproductive output and males typically mate once per season and/or per lifetime. Using scramble-mating wood frogs (Rana sylvatica), we tested whether males gain fitness benefits by mating with preferred females. We conducted choice trials (one male presented simultaneously with two females) and permitted males to mate with their preferred or non-preferred female. Offspring of preferred and non-preferred females were reared in the laboratory and field, and we quantified various fitness-relevant parameters, including survivorship and growth rates. Across multiple parameters measured, matings with preferred females produced fewer and lower-quality offspring than did those with non-preferred females. Our results are inconsistent with the idea that mate choice confers benefits on the choosing sex. We instead propose that, in scramble systems, males will be more likely to amplex females that are easier to capture, which may correlate with lower quality but increases male likelihood of successfully mating. Such male choice may not favor increased fitness when the operational sex ratio is less biased toward males in scramble mating systems but is, instead, a bet-hedging tactic benefitting males when available females are limited

Data to accompany: How does rapid body color change affect the conspicuity of lizards to their predators and conspecifics?

Predator-prey interactions drive the evolution of prey visual camouflage, but prey species also often require salience to their conspecifics for social signaling purposes. Whether rapid body color change can help to dynamically balance conspecific visibility and predator concealment, in the eyes of each group’s respective visual systems, remains poorly understood. We tested this question using water anoles (Anolis aquaticus), a small lizard that uses rapid dark-to-light body color change to visually camouflage itself from its avian predators across diverse microhabitats. We used digital image analysis and visual modeling to assess the effectiveness of color-matching camouflage in A. aquaticus, as perceived by anoles and avian predators. Our findings reveal that A. aquaticus body coloration was perceived similarly by both groups. However, sex-specific differences in overall salience emerged, with males less variable in their color matching across microhabitats compared to females. Females showed reduced color matching in their lighter phase, possibly linked to their increased refuge-seeking behavior. In contrast, males may rely more heavily on close-range camouflage possibly due to their increased exposure during territorial defense, potentially explaining the observed correlation of body size and color matching. We highlight the context-dependence of color change, with sex-specific differences and microhabitat substantially affecting its function

Size-assortative mating in explosively breeding species: a case study of adaptive male mate choice in an anuran

Exploration of size-assortative mating (SAM) in animals has led to a near consensus that it arises through non-adaptive mechanisms, such as preference for large females combined with a large male advantage during intrasexual competition. Although such “apparent” SAM is well explored, whether SAM arises because of specific preferences for size-matched mates has been less thoroughly considered. We tested for “preference-based” SAM in an explosively breeding anuran (Rana sylvatica), quantifying how male and female size affected fertilization and if males preferred size-matched females. We found that size mismatch severely reduced fertilization rates. Furthermore, males preferred size-matched, not larger, females in mate choice trials. Because males that mated with much larger females fertilized fewer eggs overall than they would have with size-matched females, male preference for size-matched females is likely adaptive. Our results expand understanding of the mechanisms underlying SAM, suggesting that multiple mechanisms may simultaneously cause size-assortative mating patterns to emerge