Researcher ORCID Identifier

https://orcid.org/0009-0002-2392-5615

Graduation Year

2026

Document Type

Open Access Senior Thesis

Degree Name

Bachelor of Science

Department

The Department of Natural Sciences

Second Department

Biology

Reader 1

Ashley Heers

Reader 2

Donald McFarlane

Terms of Use & License Information

Terms of Use for work posted in Scholarship@Claremont.

Rights Information

© 2026 Eli P Laloudakis

Abstract

When we think of birds, we think of flight. Because of this, scientific research often focuses on how birds evolved flight and how their wings function during flight. However, not all birds can fly or fly well, as wings wax and wane on developmental, seasonal, and evolutionary time scales (Dial and Heers 2021). Consequently, rudimentary wings can be found in developing birds, secondarily flightless or semiflightless birds, birds that undergo simultaneous molts, and extinct theropods with “protowings” (structures that preceded fully functional wings). Secondarily flightless and semiflightless birds often evolve where there is no/low predation, abundant year-round food supply, and mild climates.

The proposed study aims to address how semiflightless birds specifically compensate for their limited flight, whether that be through increasing leg investment, camouflaging or secretive habits, and/or finding alternative refugia that have low predation. Anatomical and performance measures would address whether these birds compensate by shifting from primarily wing to leg-based locomotion, accompanied by “better” and “bigger” legs. This study will measure wing area and feather features, bone dimensions, and muscle mass and/or length. Performance will be measured during locomotive behaviors such as vertical takeoff (VT), controlled flapping descent (CFD), wing-assisted incline running (WAIR), and steaming (S). Performance is defined as velocity and relative force production (VT, CFD, S) and angle of ascent (WAIR). Camouflaging and/or secretive habits and habitat use (refugia) will be studied through trail cams, observation, and further research.

The study would take place at Pitzer College’s Firestone Center for Restoration Ecology (FCRE) in Barú, Costa Rica, and would examine five semiflightless birds: the Crested Guan (Penelope purpurascens), Smooth-billed Ani (Crotophaga ani), Groove-billed Ani (Crotophaga sulcirostris), Least Grebe (Tachybaptus dominicus), and the Streak-chested Antpitta (Hylopezus perspicillatus). By enhancing understanding of variation in the avian body plan, this study would improve our ability to effectively conserve these birds, which are particularly vulnerable to the effects of climate change, habitat fragmentation, and introduced predators.

Download

Share

COinS