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Developmental plasticity can occur at any life stage, but plasticity that acts early in development may give individuals a competitive edge later in life. Here, we asked if early (pre-feeding) exposure to a nutrient-rich resource impacts hatchling morphology in Mexican spadefoot toad tadpoles, Spea multiplicata . A distinctive carnivore morph can be induced when tadpoles eat live fairy shrimp. We investigated whether cues from shrimp––detected before individuals are capable of feeding––alter hatchling morphology such that individuals could potentially take advantage of this nutritious resource once they begin feeding. We found that hatchlings with early developmental exposure to shrimp were larger and had larger jaw muscles––traits that, at later stages, increase a tadpole's competitive ability for shrimp. These results suggest that early developmental stages can assess and respond to environmental cues by producing resource-use phenotypes appropriate for future conditions. Such anticipatory plasticity may be an important but understudied form of developmental plasticity.
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This content will become publicly available on May 27, 2026
Flamingos use their L-shaped beak and morphing feet to induce vortical traps for prey capture
Flamingos feature one of the most sophisticated filter-feeding systems among birds, characterized by upside-down feeding, comb-like lamellae, and a piston-like tongue. However, the hydrodynamic functions of their L-shaped chattering beak, S-curved neck, and distinct behaviors such as stomping and feeding against the flow remain a mystery. Combining live flamingo experiments with live brine shrimp and passive particles, bioinspired physical models, and 3D CFD simulations, we show that flamingos generate self-induced vortical traps using their heads, beaks, and feet to capture agile planktonic prey in harsh fluid environments. When retracting their heads rapidly (~40 cm/s), flamingos generate tornado-like vortices that stir up and upwell bottom sediments and live shrimp aided by their L-shaped beak. Remarkably, they also induce directional flows (~7 cm/s) through asymmetric beak chattering underwater (~12 Hz). Their morphing feet create horizontal eddies during stomping, lifting, and concentrating sediments and brine shrimp, while trapping fast-swimming invertebrates, as confirmed by using a 3D-printed morphing foot model. During interfacial skimming, flamingos produce a vortical recirculation zone at the beak’s tip, aiding in prey capture. Experiments using a flamingo-inspired particle collection system indicate that beak chattering improves capture rates by ~7×. These findings offer design principles for bioinspired particle collection systems that may be applied to remove pollutants and harmful microorganisms from water bodies.
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- PAR ID:
- 10617983
- Publisher / Repository:
- PNAS
- Date Published:
- Journal Name:
- Proceedings of the National Academy of Sciences
- Volume:
- 122
- Issue:
- 21
- ISSN:
- 0027-8424
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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