What is Convergent: Definition and 334 Discussions

Convergent evolution is the independent evolution of similar features in species of different periods or epochs in time. Convergent evolution creates analogous structures that have similar form or function but were not present in the last common ancestor of those groups. The cladistic term for the same phenomenon is homoplasy. The recurrent evolution of flight is a classic example, as flying insects, birds, pterosaurs, and bats have independently evolved the useful capacity of flight. Functionally similar features that have arisen through convergent evolution are analogous, whereas homologous structures or traits have a common origin but can have dissimilar functions. Bird, bat, and pterosaur wings are analogous structures, but their forelimbs are homologous, sharing an ancestral state despite serving different functions.
The opposite of convergence is divergent evolution, where related species evolve different traits. Convergent evolution is similar to parallel evolution, which occurs when two independent species evolve in the same direction and thus independently acquire similar characteristics; for instance, gliding frogs have evolved in parallel from multiple types of tree frog.
Many instances of convergent evolution are known in plants, including the repeated development of C4 photosynthesis, seed dispersal by fleshy fruits adapted to be eaten by animals, and carnivory.

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  1. A

    MHB Prove No Uniformly Convergent Subsequence: Functional Sequence

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  2. A

    MHB Sequence of continuous functions convergent to an increasing real function

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  3. A

    Using the ratio test to figure if the series is convergent

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  4. PhysicoRaj

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  5. M

    MHB Telling if a series is convergent or divergent?

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  6. J

    Determine whether the integral is divergent. If convergent, evaluate.

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  7. G

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  8. P

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  9. A

    The title could be: Uniform Convergence of f_n(x) = nx^n(1-x) on [0,1]?

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  10. P

    Does the Maximum of Two Convergent Series Also Converge?

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  11. binbagsss

    Quick convergent series question.

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  12. J

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  13. P

    Convergent sequence in compact metric space

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  14. B

    Does the Convergence of a Series Depend on the Values of its Terms?

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  15. S

    Absolutely convergent but not uniformly convergent

    I'm trying to show \sum_{k=1}^{\infty}2^{k}sin(\frac{1}{3^{k}x}) does not converge uniformly on any (epsilon, infinity) now I was able to show that it converges absolutely for x nonzero, by getting it in the form \sum_{k=1}^{\infty}x\left(\frac{2}{3}\right)^{k}\frac{sinx}{x} and so the sinx/x...
  16. P

    Finding sum of convergent series.

    Hi, I have determined, correctly I believe, that the following series converges: 1/[(3n-2)(3n+1)] Now I am asked to determine its sum. I have tried separating it into two subseries, but each time got a p-series with p=1, hence to no avail. The answer should be 1/3, but how may it be...
  17. H

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  18. G

    Does a uniformly convergent sequence imply a convergent series

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  19. C

    Does the value of p-q affect the uniform convergence of fn on [0,1-ε]?

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  20. B

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  21. N

    Rearranging terms of a conditionally convergent series

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  22. M

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  23. G

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  24. S

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  25. S

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  26. L

    Cos(2n)/n^0.5 convergent or not?

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  27. P

    Proving a sequence is convergent.

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  28. B

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  29. G

    Convergent sequences in Cartesian product of vector spaces

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  30. U

    A general convergent series under different circumstances.

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  31. B

    Convergent sequence and limit points

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  32. Ryuzaki

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  33. D

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  34. S

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  35. K

    Show that the series is convergent

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  36. K

    Series - convergent or divergent?

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  37. A

    Determine the limit of the convergent sequence

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  38. C

    MHB Is this power series a convergent series?

    Hi everyone! I have got this series in a part of my research. I need to check if this is a convergent series and if so, what is the radius of the convergence? Here is the series.. \[\sum_{i=0}^{\infty}(-1)^{i}{b-1\choose i}B(y+ac+ci,\,n-y+1)\] Sorry if my LateX code is not visible( I am...
  39. G

    Problem with convergent sequences

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  40. X

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  41. K

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  42. K

    Determine Absolute Convergence, Conditionally Convergent, or Divergent

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  43. joe_cool2

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  44. E

    Determine Convergent or Divergent

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  45. E

    Proving Convergent Sequence Limit Equality

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  46. H

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  47. M

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  48. M

    Is the sequence {n} convergent? (I'm thinking that it is not)

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  49. I'm Awesome

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  50. E

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