Q.Mention one example each from plants and animals exhibiting divergent evolution.

Showing the 12 most recent of 14 on this concept.

1. CBSE 2026Set ANNUAL1 mark
   Q.Fill in the blank: When more than one adaptive radiation have occurred in an isolated geographical area, this is called as ______ evolution.

   ›Reveal solutionSolution

   When more than one adaptive radiation occurs independently within the same isolated geographical area, giving structurally similar (analogous) end forms, it is termed convergent evolution.

   Adaptive radiation is the evolution of different species from a common ancestor within one geographical area, each adapting to a different niche (e.g., Darwin's finches on the Galapagos). When such radiation happens more than once, independently, within one isolated area, producing organisms of different ancestry that come to resemble each other in form due to similar adaptive pressures (analogous structures), this is called convergent evolution - the classic textbook example being Australian marsupials and placental mammals evolving similar body forms independently.

   ✓Final answer

   Convergent evolution.

2. CBSE 2026Set ANNUAL1 markMCQ
   Q.Darwin observed different types of beaks in finches adapted to different feeding habits on the Galapagos Islands. This diversity provides evidence for :

   (a) intraspecific competition.

   (b) interspecific competition.

   (c) origin of species by natural selection.

   (d) origin of species by mutation.

   ›Reveal solutionSolution

   Darwin's finches show a variety of beak shapes evolved from one ancestral stock to suit different foods — evidence for origin of species by natural selection (adaptive radiation), so (c) is correct.

   In the CBSE/NCERT Evolution chapter, Darwin observed many finch species on the Galapagos Islands. From an original seed-eating ancestor, populations diversified into forms with different beaks suited to different feeding habits (insectivorous, seed-eating, etc.). This process — many species radiating from a common ancestor into different ecological niches — is adaptive radiation, the direct outcome of natural selection favouring the best-adapted variants in each niche.

   ✓Final answer

   (c) The beak diversity of Darwin's finches is evidence for the origin of species by natural selection.

3. CBSE 2025Set 57/6/11 markMCQ
   Q.In his observations of small black birds in the Galapagos Islands, Darwin found that all the finches arose from the original ancestor : (A) Insect-eating finches (B) Seed-eating finches (C) Cactus-eating finches (D) Fruit-eating finches

   ›Reveal solutionSolution

   Darwin's Galapagos finches all descended from an original seed-eating finch ancestor that colonized the islands and then diversified into multiple ecological niches.

   When Darwin visited the Galapagos Islands during the voyage of the HMS Beagle, he encountered a remarkable group of small black birds that would later become one of the most celebrated examples of evolution in action. These finches, though superficially similar, showed striking differences in their beak shapes and sizes, each adapted to different food sources on the various islands.

   The key insight Darwin eventually developed was that all these diverse finch species shared a common origin. The ancestral finch that first arrived on the Galapagos from the South American mainland was a seed-eating bird. This makes biological sense: seed-eaters are generalist feeders with robust beaks capable of handling a variety of foods, making them well-suited to colonize new, unpredictable environments.

   Once established on the islands, this founding population faced a landscape rich in unexploited resources but poor in competition. Different islands offered different opportunities—some had abundant insects, others cacti, still others various seeds and fruits. Over successive generations, natural selection favored individuals whose beak shapes happened to be better suited to the locally available food. A finch with a slightly longer, more pointed beak could probe bark for insects more effectively. One with a stout, powerful beak could crack tough seeds. Another with a specialized shape could feed on cactus flowers and pulp.

   Important

   This process—where a single ancestral species rapidly diversifies into multiple forms, each adapted to a different ecological niche—is called adaptive radiation. The Galapagos finches are a textbook case because the islands provided isolated environments where different selection pressures could act independently.

   The original seed-eating finch thus gave rise to the entire array of finch species Darwin observed: insect-eaters with slender beaks, large ground finches with massive seed-crushing beaks, cactus finches with probing beaks, and many others. Each represents a different evolutionary experiment, all stemming from that single colonizing ancestor.

   ✓Final answer

   In short, Darwin's Galapagos finches all arose from an original seed-eating finch ancestor (option B), which diversified through adaptive radiation into the various specialized forms he observed across the islands.

4. CBSE 2025Set ANNUAL1 markMCQ
   Q.Assertion(A): Adaptive radiation led to evolution of many varieties of finches. Reason(R): Originally finches were seed eaters.

   (a) Both (A) and (R) are true and (R) is the correct explanation of (A)

   (b) Both (A) and (R) are true but (R) is not the correct explanation of (A)

   (c) (A) is true but (R) is false

   (d) Both (A) and (R) are false

   ›Reveal solutionSolution

   Both statements about Darwin's finches are factually true, but their original seed-eating habit does not explain why adaptive radiation happened — geographic isolation and diversification into new niches does.

   Adaptive radiation is the process by which species evolve within a relatively short period of geological time from a common ancestor into a variety of forms, all adapted to different ecological niches available in a new/isolated environment, without migrating to other areas. Darwin's finches, found on the Galapagos Islands, are a classic textbook example — a single ancestral finch species, upon reaching the isolated islands, radiated into several different species, each adapted to a different food source (some seed-eating, some insect-eating, some cactus-feeding), primarily distinguished by differences in their beak shape/size suited to that specific diet.

   • Assertion (A) is true — adaptive radiation did lead to the evolution of many varieties of finches.
   • Reason (R) — "Originally finches were seed eaters" — is also a factually true historical detail (the ancestral finch species that colonised the islands was indeed seed-eating), but it is not the correct explanation for why adaptive radiation (the diversification into many finch species/forms) occurred. The actual explanation for adaptive radiation lies in the finches' geographic isolation on the various Galapagos islands and their subsequent diversification to exploit different unoccupied ecological niches/food sources (seeds, insects, cactus, etc.) available on the islands — not merely the fact that they originally ate seeds.

   So both statements are individually true, but R does not correctly explain A.

   ✓Final answer

   (b) Both (A) and (R) are true but (R) is not the correct explanation of (A)

5. CBSE 2024Set ANNUAL1 markMCQ
   Q.Darwin's finches is an example of

   (a) Convergent evolution

   (b) Parallel evolution

   (c) Adaptive radiation

   (d) Chemical evolution

   ›Reveal solutionSolution

   Darwin's finches are the classic textbook example of adaptive radiation — divergent evolution of many species from one ancestral form within the same isolated geographic area.

   When Darwin visited the Galapagos Islands, he found many kinds of finches, differing mainly in the size and shape of their beaks, on a small isolated island. Starting from a single seed-eating ancestral finch species that colonised the islands, different populations adapted to different food sources (seeds, insects, buds, cactus flowers) available on the islands, evolving different beak shapes suited to each diet — a single ancestral species radiating into many species within one geographical area is called adaptive radiation. Convergent evolution, in contrast, is when unrelated organisms in different places evolve similar structures due to similar habitats (e.g., Australian marsupials and placental mammals showing analogous body forms).

   ✓Final answer

   (c) Adaptive radiation.

6. CBSE 2024Set ANNUAL1 mark
   Q.Give one example of adaptive radiation.

   ›Reveal solutionSolution

   Adaptive radiation is the evolution of many species from a common ancestor, each adapted to a different niche in the same geographic area; Darwin's finches on the Galapagos Islands are the classic example.

   When a single ancestral finch species reached the isolated Galapagos Islands, it found many vacant ecological niches with no competitors. Over generations, its descendants diversified into several species differing mainly in beak size and shape, each specialised for a different food source (seed-crushing, insect-eating, cactus-feeding, etc.) - all evolving in one place from one ancestor, which is the defining feature of adaptive radiation. (Australian marsupials radiating into forms resembling placental mammals - kangaroo, marsupial 'wolf', etc. - is another valid textbook example.)

   ✓Final answer

   Darwin's finches (Galapagos Islands) - one ancestral finch species radiated into many species with beaks adapted to different food sources.

7. CBSE 2023Set ANNUAL1 mark
   Q.Where Darwin's Finches are found?

   ›Reveal solutionSolution

   Darwin's finches inhabit the Galapagos Islands in the Pacific Ocean.

   Darwin's finches are a group of about 14 closely related species of finches that Charles Darwin observed and collected during the voyage of HMS Beagle. They are found on the Galapagos Islands, a volcanic archipelago in the Pacific Ocean off the coast of Ecuador. Their varying beak shapes and sizes, adapted to different food sources available on different islands, became key evidence for Darwin's theory of adaptive radiation and natural selection.

   ✓Final answer

   The Galapagos Islands

8. CBSE 2023Set ANNUAL1 mark
   Q.Give an example of adaptive radiation.

   ›Reveal solutionSolution

   Adaptive radiation is the evolution of many different species from a common ancestor, each adapted to a different niche in the same geographical area; Darwin's finches are the textbook example.

   When a species colonises a new, relatively unoccupied habitat (like an island), it can diversify into multiple descendant species, each adapting to exploit a different available niche/resource — this is adaptive radiation. On the Galapagos Islands, a single ancestral finch species that arrived from the mainland diversified into more than a dozen species, differing mainly in beak size and shape, each suited to a different diet (seed-crushing, insect-eating, cactus-flower feeding, etc.). A comparable Indian/Australian example is the marsupial radiation seen in Australia.

   ✓Final answer

   Darwin's finches (Galapagos finches) — one ancestral species radiating into many species with differently adapted beaks.

9. CBSE 2022Set ANNUAL1 markMCQ
   Q.Human hands, the wings of a bat, and the flippers of a seal express

   (a) vestigial organs

   (b) analogous organs

   (c) evolutionary organs

   (d) homologous organs

   ›Reveal solutionSolution

   These forelimbs share a common structural plan, so they are homologous organs (D).

   Homologous organs have the same fundamental structure and embryonic origin but perform different functions. The forelimbs of a human (grasping), a bat (flying) and a seal (swimming) are all built on the same underlying pentadactyl (five-fingered) bone arrangement — humerus, radius, ulna, carpals, metacarpals and phalanges — modified for different uses. This common ancestry with divergent function is evidence of divergent evolution.

   Analogous organs, by contrast, have different structure but similar function (e.g. wings of insects and birds). Hence these forelimbs are homologous.

   ✓Final answer

   (D) homologous organs.

10. CBSE 2020Set NC1 markMCQ
    Q.Variety of beaks of finches that Darwin found in Galapagos islands was due to

    (a) adaptive radiation

    (b) convergent evolution

    (c) genetic drift

    (d) artificial selection

    ›Reveal solutionSolution

    Darwin's Galapagos finches diversified from a single common ancestral species into many different species, each with a beak shape adapted to exploiting a different food resource — the textbook example of adaptive radiation.

    Reasoning

    Adaptive radiation is the evolutionary process by which a single ancestral species, upon colonising a new, geographically isolated environment offering a variety of unoccupied ecological niches, diversifies rapidly into multiple descendant species, each becoming adapted (via natural selection) to a different niche/mode of life. Charles Darwin observed exactly this pattern among the finches of the Galapagos Islands: a single ancestral finch species that had colonised the islands diversified into many different species, each evolving a distinctly-shaped beak suited to a particular food source (e.g. seed-crushing, insect-probing, or cactus-feeding beaks) — this is the textbook illustration of adaptive radiation. This differs from convergent evolution (b), where unrelated species independently evolve similar features due to similar environmental pressures (the opposite pattern); genetic drift (c), a random, non-selective change in allele frequencies; and artificial selection (d), which involves deliberate selection by humans, not natural, unguided divergence.

    ✓Final answer

    (a) adaptive radiation

11. CBSE 2019Set 57/2/11 mark
    Q.Mention one example each from plants and animals exhibiting divergent evolution.

    ›Reveal solutionSolution

    Divergent evolution occurs when related species adapt to different environments, developing distinct traits from a common ancestor — seen in the varied spines, tendrils and leaves of Opuntia, Bougainvillea and Cucurbita (all modified leaves), and in Darwin's finches, whose beaks diversified for different food sources across the Galápagos Islands.

    Divergent evolution is the process by which organisms sharing a common ancestor evolve along separate paths, accumulating differences as they adapt to distinct ecological niches or environments. The starting point is homology — structures that are anatomically similar because they were inherited from the same ancestor, even though they may now serve entirely different functions. Over time, natural selection moulds these homologous structures in divergent directions, producing what we call adaptive radiation when the divergence is rapid and produces multiple new forms.

    Plant example: Modified leaves in different species

    Consider three familiar plants: Opuntia (the prickly pear cactus), Bougainvillea, and Cucurbita (the gourd family, which includes pumpkins and cucumbers). In each, the leaf has been modified to serve a completely different purpose, yet all three structures are homologous — they share the same developmental origin as foliage leaves.

    • In Opuntia, leaves have become sharp spines. This adaptation reduces water loss in arid desert environments and deters herbivores from feeding on the succulent stem, which has taken over the photosynthetic role.
    • In Bougainvillea, leaves have transformed into colourful bracts — the vivid pink, purple or orange structures we admire are not petals but modified leaves that attract pollinators to the small, inconspicuous flowers nestled within.
    • In Cucurbita, leaves have evolved into tendrils, slender coiling structures that help the climbing vine anchor itself to supports and reach sunlight in crowded habitats.

    The common ancestry is evident in the developmental blueprint, but the selective pressures of different environments — water scarcity, pollinator attraction, structural support — have driven the divergence.

    Animal example: Darwin's finches

    The textbook case of divergent evolution in animals comes from the finches of the Galápagos archipelago, famously studied by Charles Darwin. All the finch species on these islands descended from a common ancestral finch that arrived from the mainland. Once isolated on different islands with varying food resources, populations began to diverge.

    The most striking divergence appears in beak morphology. Some finches developed large, robust beaks suited to cracking hard seeds. Others evolved slender, pointed beaks for probing flowers or catching insects. Still others acquired medium-sized beaks for a generalist diet. Each beak shape is an adaptation to a specific feeding niche, yet all are variations on the same underlying skeletal and muscular architecture inherited from the common ancestor.

    Important

    Divergent evolution produces homologous structures — anatomically similar because of shared ancestry, functionally different because of adaptation. This contrasts with convergent evolution, where unrelated organisms independently evolve similar traits (analogous structures) in response to similar environmental challenges.

    The power of divergent evolution lies in its ability to generate biodiversity from a single ancestral stock. When a founding population encounters a range of empty or underexploited niches, natural selection favours different traits in different subpopulations, and over many generations the descendants become distinct species, each finely tuned to its particular way of life.

    ✓Final answer

    In short, divergent evolution is exemplified by the modified leaves of Opuntia (spines), Bougainvillea (bracts) and Cucurbita (tendrils) in plants, and by the varied beak shapes of Darwin's finches in animals — all homologous structures reshaped by natural selection for different ecological roles.

12. CBSE 2018Set ANNUAL1 mark
    Q.Longer toes and long prehensile tail indicate which adaptation?

    ›Reveal solutionSolution

    Arboreal adaptation — longer, grasping toes and a long prehensile tail evolved as adaptations for gripping branches, climbing and balancing in a tree-dwelling (arboreal) habitat, characteristic of early primates.

    Long grasping toes and a prehensile tail are adaptations for life in trees (arboreal habit).

    Early primates evolved from ground-dwelling ancestors that took to living in trees, and their skeleton shows a suite of features suited to this arboreal lifestyle. Longer, more flexible and often opposable toes/digits give a firm grip on branches of varying thickness, while a long, muscular, prehensile tail (in New World monkeys, for example) can coil tightly around a branch, acting almost as a fifth limb for support and balance while climbing, leaping and reaching for food among the branches. These traits are cited in primate/human-evolution study as evidence of the arboreal phase in primate ancestry, which also favoured other trends like binocular/stereoscopic vision and a mobile shoulder joint.

    ✓Final answer

    Longer toes and a long prehensile tail indicate adaptation to an arboreal (tree-dwelling) mode of life.