More Like this

1. Leaf Conditions Affect the Landing Success of Fallen Tropical Ants

   https://doi.org/10.1111/btp.70107  

   Seiler, Andrew R; Stark, Alyssa Y; Yanoviak, Stephen P (September 2025, Biotropica)

   ABSTRACT Falling to the ground is hazardous for arboreal ants. Workers of six ant species dropped onto leaves had the lowest landing success on inclined and wet leaves; epiphyll presence and ant body size had no effect. Consequently, landing on leaves in wet forests apparently is challenging for arboreal ants. 

   more » « less
2. Katydids shift to higher-stability gaits when climbing inclined substrates

   https://doi.org/10.1093/icb/icaf133  

   Riiska, Calvin A; Harrison, Jacob S; Thompson, Rebecca D; Nina, Jaime Quispe; Gallice, Geoffrey R; Rieser, Jennifer M; Bhamla, Saad (August 2025, Integrative And Comparative Biology)

   Abstract When terrestrial organisms locomote in natural settings, they must navigate complex surfaces that vary in incline angles and substrate roughness. Variable surface structures are common in arboreal environments and can be challenging to traverse. This study examines the walking gait of katydids (Tettigoniidae) as they traverse a custom-built platform with varying incline angles (30○, 45○, 60○, 75○, 90○) and substrate roughness (40, 120, and 320 grit sandpaper). Our results show that katydids walk more slowly as the incline angle increases and as katydid mass increases, with a decrease of around 0.3 body lengths per second for every 1○ increase in incline. At steeper inclines and larger sizes, katydids are also less likely to use an alternating tripod gait, opting instead to maintain more limbs in contact with the substrate during walking. Katydids also increased average duty factor when climbing steeper inclines and with increasing body mass. However, substrate roughness did not affect walking speed or gait preference in our trials. These findings provide insights into how environmental factors influence locomotor strategies in katydids and enhance our understanding of effective locomotor strategies in hexapods. 

   more » « less
3. The Effects of Roughness and Wetness on Salamander Cling Performance

   https://doi.org/10.1093/icb/icaa110  

   O’Donnell, Mary Kate; Deban, Stephen M (July 2020, Integrative and Comparative Biology)

   null (Ed.)

   Synopsis Animals clinging to natural surfaces have to generate attachment across a range of surface roughnesses in both dry and wet conditions. Plethodontid salamanders can be aquatic, semi-aquatic, terrestrial, arboreal, troglodytic, saxicolous, and fossorial and therefore may need to climb on and over rocks, tree trunks, plant leaves, and stems, as well as move through soil and water. Sixteen species of salamanders were tested to determine the effects of substrate roughness and wetness on maximum cling angle. Substrate roughness had a significant effect on maximum cling angle, an effect that varied among species. Substrates of intermediate roughness (asperity size 100–350 µm) resulted in the poorest attachment performance for all species. Small species performed best on smooth substrates, while large species showed significant improvement on the roughest substrates (asperity size 1000–4000 µm), possibly switching from mucus adhesion on a smooth substrate to an interlocking attachment on rough substrates. Water, in the form of a misted substrate coating and a flowing stream, decreased cling performance in salamanders on smooth substrates. However, small salamanders significantly increased maximum cling angle on wetted substrates of intermediate roughness, compared with the dry condition. Study of cling performance and its relationship to surface properties may cast light onto how this group of salamanders has radiated into the most speciose family of salamanders that occupies diverse habitats across an enormous geographical range. 

   more » « less
4. Investigating the perception of risks during arboreal locomotion in wild and captive primates

   Schapker, Nicole M; Myers, Lydia C; Janisch, Judith; Matar, Ahmad; Pham, Julie; Miller, Aidan; Boghdady, Abdelrahman; Shapiro, Liza J; Young, Jesse W (March 2025, American Journal of Biological Anthropology)

   Much research on primate locomotor performance in arboreal settings focuses on how primate morphology allows them to navigate substrates that vary in diameter, orientation, and compliance. However, little prior research has considered how these and other environmental factors - such as substrate height and light availability - may also affect locomotor behavior by altering how risky a given substrate is perceived to be. To investigate the relationship between risk perception and locomotor performance, we video-recorded four species of wild lemur (Ranomafana National Park), three species of wild cercopithecoid monkeys (Kibale National Park), and four species of captive lemur (Duke Lemur Center). We test the general hypothesis that primates should change their gaits and engage in exploratory behaviors – using touch and sight as guides – to increase stability in precarious settings. Augmenting our prior study showing that some lemurs change their locomotion when moving high in the canopy, we present new data showing that wild lemurs and monkeys frequently cross gaps between substrates and transition between locomotor modes without pause. In the investigation on captive lemurs, we examine whether variations in branch diameter, compliance, orientation, and light availability influence the paths lemurs choose to take. Preliminary results suggest that lemurs tend to avoid the most precarious substrates (i.e., the most narrow and compliant) regardless of lighting conditions. Overall, this research indicates that primates are able to make quick and accurate judgements about locomotor safety in the context of ongoing arboreal locomotion. 

   more » « less
5. Reaching new heights: Arboreal ant diversity in a North American temperate forest ecosystem

   https://doi.org/10.1111/icad.12788  

   Kirchner, Michelle; Sorenson, Clyde; Blaimer, Bonnie B; Youngsteadt, Elsa (November 2024, Insect Conservation and Diversity)

   Abstract Most canopy insect research takes place in tropical forests, where communities are highly vertically stratified. However, temperate forest canopies also provide critical resources to many species and are under intense pressure from global change drivers. The relative lack of knowledge regarding temperate canopy insect ecology impedes our forest management and conservation decisions such that we may be losing temperate canopy biodiversity before we know it exists.We directly compared ant diversity and community composition on the ground and in the tree canopy of North American temperate deciduous forests for the first time. We also evaluated two canopy sampling methods—baits and hand collections.We collected 34 ant species from 102 trees across seven sites. Ant diversity was greater on the ground than in the canopy, and species turnover created distinct communities across vertical strata. Only 12% of species were exclusively arboreal, but 47% were collected in both strata, indicating the canopy is an important resource for temperate ants, even if they are not restricted there.Baiting and hand‐collecting recovered similar species richness, but whether baits captured a subset of hand‐collected species or a unique assemblage was site‐dependent. Nevertheless, we suggest that these methods are most effective in conjunction.Hand collection allowed us to document arboreal nests of 10 species, including the invasive needle ant,Brachyponera chinensis, which was previously thought to be strictly terrestrial.Our results emphasise the importance of including the canopy in temperate forest ecology and conservation assessments. 

   more » « less