Question

For decades, the prevailing paleontological narrative posited that the earliest tetrapods evolved robust, limb-like appendages primarily as an adaptive response to receding Devonian waterways, allowing these creatures to traverse desiccated landmasses in search of new aquatic habitats. This "shrinking puddle" hypothesis, popularized in the mid-twentieth century, essentially characterized limbs as an innovation driven by the necessity of returning to water. However, recent sedimentological analyses of late Devonian deposits reveal that the earliest known tetrapod fossils are concentrated in strata indicative of heavily vegetated, permanent wetland ecosystems, rather than ephemeral pools subject to seasonal drought. Concurrently, biomechanical modeling of taxa such as *Acanthostega* indicates that their forelimbs, while featuring recognizable digits, lacked the structural articulation necessary to support the animal's full weight on terrestrial substrate. Instead, these appendages were optimally oriented for navigating the dense, submerged root systems and detritus characterizing their immediate environments. This morphological configuration suggests that what later became the definitive adaptation for terrestrial locomotion initially emerged entirely within an aquatic context, conferring a predatory advantage in structurally complex underwater biomes.

Based on the passage, if the "shrinking puddle" hypothesis were entirely accurate, one would most reasonably expect to find which one of the following?