Evolutionary Biology Mock Tests

The following passage is an excerpt from an article about evolutionary biology. Convergent evolution is the process by which unrelated organisms independently evolve similar traits as they adapt to similar environments or ecological niches. This phenomenon provides compelling evidence for the power of natural selection to shape organisms in predictable ways. A classic example is the evolution of wings in bats, birds, and pterosaurs. These three groups are not closely related—birds are dinosaurs, bats are mammals, and pterosaurs are a separate group of flying reptiles—yet all three independently evolved wings capable of powered flight. The underlying structures of these wings are quite different: bird wings consist of feathers supported by bones, bat wings are membrane stretched between elongated finger bones, and pterosaur wings were membrane supported by a single elongated finger. Despite these structural differences, all three wings serve the same function and share similar aerodynamic properties. Another well-known example is the streamlined body shape of sharks (fish), dolphins (mammals), and ichthyosaurs (extinct reptiles). All three live in aquatic environments and have independently evolved torpedo-shaped bodies, dorsal fins, and flattened tails for efficient swimming. The underlying anatomy is strikingly different—sharks have cartilaginous skeletons, dolphins have bony skeletons and breathe air, and ichthyosaurs had specialized scales—but the external similarities are remarkable. Convergent evolution also occurs at the molecular level. For instance, the protein crystallin, which is used in the lenses of vertebrate eyes to focus light, had previously been unknown in biological systems until it was discovered that these proteins—previously known as metabolic enzymes—have been independently recruited in multiple lineages to serve the optical function of transparency. This suggests that evolution often works by repurposing existing materials rather than creating new ones from scratch. According to the passage, what do the wings of bats, birds, and pterosaurs have in common?

The following passage is an excerpt from an article about evolutionary biology. Convergent evolution is the process by which unrelated organisms independently evolve similar traits as they adapt to similar environments or ecological niches. This phenomenon provides compelling evidence for the power of natural selection to shape organisms in predictable ways. A classic example is the evolution of wings in bats, birds, and pterosaurs. These three groups are not closely related—birds are dinosaurs, bats are mammals, and pterosaurs are a separate group of flying reptiles—yet all three independently evolved wings capable of powered flight. The underlying structures of these wings are quite different: bird wings consist of feathers supported by bones, bat wings are membrane stretched between elongated finger bones, and pterosaur wings were membrane supported by a single elongated finger. Despite these structural differences, all three wings serve the same function and share similar aerodynamic properties. Another well-known example is the streamlined body shape of sharks (fish), dolphins (mammals), and ichthyosaurs (extinct reptiles). All three live in aquatic environments and have independently evolved torpedo-shaped bodies, dorsal fins, and flattened tails for efficient swimming. The underlying anatomy is strikingly different—sharks have cartilaginous skeletons, dolphins have bony skeletons and breathe air, and ichthyosaurs had specialized scales—but the external similarities are remarkable. Convergent evolution also occurs at the molecular level. For instance, the protein crystallin, which is used in the lenses of vertebrate eyes to focus light, had previously been unknown in biological systems until it was discovered that these proteins—previously known as metabolic enzymes—have been independently recruited in multiple lineages to serve the optical function of transparency. This suggests that evolution often works by repurposing existing materials rather than creating new ones from scratch. According to the passage, what do the wings of bats, birds, and pterosaurs have in common?