Soru

The following passage is excerpted from an academic article on evolutionary biology.

For over a century, paleontologists and evolutionary biologists have debated the origins of avian flight, a major evolutionary transition that transformed vertebrate ecology. Historically, this discourse was dominated by two mutually exclusive frameworks: the "arboreal" (trees-down) hypothesis and the "cursorial" (ground-up) hypothesis. The arboreal model, first popularized in the nineteenth century, posits that early proto-birds climbed trees and subsequently learned to glide, eventually evolving powered flight. While this narrative offers a seductively intuitive progression from leaping to gliding to flying, it has increasingly foundered on the rocks of biomechanical analysis. Critics rightly point out that the hindlimb anatomy of Archaeopteryx and its closest theropod relatives shows distinct adaptations for terrestrial running, not arboreal perching. Thus, despite its lingering popularity in introductory textbooks, the arboreal theory is a speculative construct unsupported by the morphological data.

Conversely, the cursorial hypothesis, championed most notably by John Ostrom in the 1970s, argues that flight evolved from small, bipedal, terrestrial theropods that used their feathered forelimbs to catch insects or gain thrust while running. Ostrom’s work was unequivocally monumental in establishing the dinosaurian origin of birds. However, the aerodynamic viability of the cursorial model remains highly suspect. Biophysicists have convincingly demonstrated that the drag created by proto-wings during a terrestrial sprint would have actively hindered forward momentum long before generating sufficient lift for takeoff. We must acknowledge Ostrom's pivotal role in shifting the phylogenetic paradigm, yet we must simultaneously recognize that his aerodynamic mechanism is physically untenable.

In recent decades, the fossil record has yielded a spectacular array of feathered dinosaurs from the Liaoning province in China. Yet, contrary to expectations, these discoveries have not resolved the aerodynamic debate; instead, they have highlighted the frustrating ambiguity of static morphological evidence. A beautifully preserved fossil can tell us what feathers looked like, but it cannot definitively tell us how they functioned in a living, breathing organism interacting with gravity. The static nature of these remains forces scientists into endless cycles of inferential debate.

Fortunately, a more dynamic approach has emerged: the Wing-Assisted Incline Running (WAIR) hypothesis, proposed by Kenneth Dial. By observing extant ground birds like chukars, Dial demonstrated that developing birds use their nascent wings not to fly, but to generate aerodynamic forces that press them against steep inclines, allowing them to run up nearly vertical surfaces to escape predators. This provides a brilliant evolutionary stepping-stone: proto-wings conferred a clear survival advantage well before they were capable of sustained flight. WAIR elegantly bridges the gap between terrestrial bipedalism and powered flight without requiring the biomechanical leaps of faith demanded by both the traditional arboreal and cursorial models. It represents a paradigm shift that, by grounding evolutionary theory in observable ethological mechanics, offers the most rigorous and compelling explanation for avian flight to date.

Based on the passage, match each of the following subjects related to the study of avian flight (Left) to the phrase that best captures the author's attitude toward it (Right).