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  1. Myelinated nerves in vertebrates, annelids and crustaceans
    Myelinated nerves are an excellent biological solution and needless to say have evolved independently in several groups other than vertebrates. In each case myelination is associated with very rapid nervous conduction and often escape reactions.

  2. Hearts in cephalopods and vertebrates
    There is a striking convergence between the aorta of the cephalopod and vertebrate heart, notably in its structure and the employment of elastic proteins.

  3. Carbonic anhydrase in vertebrates, plants, algae and bacteria
    Carbonic anhydrase is extremely convergent and may have evolved as many as six times. The most familiar variants are α, β and γ carbonic anhydrases.

  4. Burrowing: from worms to vertebrates
    Quite a few adaptations are useful for burrowing into the soil. So it is not exactly surprising that they have evolved several times...

  5. Octopus and other cephalopods: convergence with vertebrates
    What could be more different from us than the alien-like octopus? Hold on. Look it in the eye and think again.

  6. Camera eyes in vertebrates, cephalopods and other animals
    Camera eyes are superb optical devices, so it is not surprising that they have evolved several times. But why, of all animals, in the brainless jellyfish? Or for that matter in a slow-moving snail?

  7. Vibrational communication in insects and spiders
    Some spiders have evolved a most remarkable method of capturing other spiders – they imitate the vibrations of insects caught in their victim’s web. And this is only one of numerous intriguing examples of vibrational communication in arthropods…

  8. Carnivorous plants
    All plants are harmless? Well, not quite - at least not when you're an insect...

  9. Agriculture in marine polychaete annelids
    Some polychaetes attach pieces of algae to their dwelling tube. Just for decoration? No, but for a much more substantial (and convergent) benefit...

  10. Vibrational communication in animals
    What on earth could an elephant or treehoppers have in common with a seismometer?

  11. Pressure sensitivity and the tactile sense (excluding the lateral line)
    The star-nosed mole is famous for, well, its nose, but do you have any idea what these peculiar 'tentacles' are for? The answer is rather touching and, of course, convergent...

  12. Foam nests in animals
    Nests crop up everywhere, but one made out of foam? Might not sound like a great idea, but it is. And no surprise, it has evolved several times...

  13. Lateral line system in fish and other animals
    Some cavefish are completely blind, so how do they manage to navigate through their environment with astonishing ease?

  14. Pufferfish (and inflation)
    Pufferfish are some of the most extraordinary fish to have evolved, especially because of their capacity to swallow water and inflate themselves to something like a football. Not only that but some representatives can be deadly to the unwary diner...

  15. Suction feeding in fish, amphibians, reptiles and aquatic mammals
    Probably everyone is familiar with the walrus, but did you know that it generates a vacuum in its mouth to suck clams out of their shells? And this is just one example of suction feeding, the feeding mode typically used by bony fish…

  16. Tetrodotoxin
    Not many foods served in a restaurant can kill you, but pufferfish is the exception. Tetrodotoxin, the toxin responsible for such culinary fatalities, reveals a fascinating story of convergent evolution...

  17. Teeth in aquatic reptiles
    Aquatic reptiles tend to display one of three dentition types, well adapted to either seize and slice large vertebrate prey, pierce and gouge slippery fish, or entrap small prey such as crustaceans.

  18. Beak structures in reptiles and birds
    Among reptile taxa with beak structures, we find several cases of convergent evolution, for example between turtles, Uromastyx lizards, a number of herbivorous dinosaurs and the tuatara (Sphenodon) of New Zealand.

  19. Venom and venom fangs in snakes, lizards and synapsids
    Although the evolution of snake fangs itself provides us with a window on convergence, the presence of fang-like teeth in lizards, therapsids and mammals provides an even broader and more remarkable perspective.

  20. Feeding in snakes and lizards
    The Turtle-headed sea snake feeds on small eggs and its feeding shows intriguing similarities to the way lizards forage, and herbivorous mammals graze and browse.

  21. Crabs: insights into convergence
    You might think of crabs mainly as food, but this group is also highly instructive in terms of convergence…

  22. Bats: Insights into convergence
    Bats show a fascinating array of convergences, from echolocation to flight to nectar feeding. Vampire bats can even detect infrared radiation, while others might be able to see into the ultraviolet end of the spectrum.

  23. Camera eyes in cubozoan jellyfish
    On each of the four club-like extensions (rhopalia) near the base of the cubozoan jellyfish bell there are two camera-eyes, one pointing upwards and the other downwards.

  24. Pharyngeal jaws in teleost fish
    One of the great evolutionary breakthroughs in the teleost fish was the conversion of some of the elements that supported the gill bars into a second set of pharyngeal teeth that complemented the oral teeth. See how a fish becomes a snake!

  25. Durophagy (hard prey-eating) in fish
    Plenty of animals have an extraordinary capacity to crush hard prey and this has evolved independently many times in the vertebrates. If you suspect it is a durophage, watch your fingers!

  26. Gliding lizards, frogs and ants
    Tree-dwelling (‘arboreal’) ants capable of controlled gliding do so when dislodged or threatened by predation. Gliding species include members of three disparate families: Myrmicinae, Pseudomyrmecinae and Formicinae.

  27. Gliding reptiles
    In the reptiles, different forms of skin membrane (called ‘patagia’) and in some extinct species, primitive feathers, have evolved convergently as adaptations for gliding.

  28. Viviparity in sauropterygians
    “The [fossilised] embryos are mostly in articulation and their distribution on each side indicates that female Keichousaurus hui had a pair of oviducts as in ichthyosaurs and many extant lizards.” Y. Cheng et al. (2003) Nature vol. 432, p.383

  29. Viviparity in mosasaurs
    An exceptionally preserved gravid female of the aigalosaur Carsosaurus contains at least at least four advanced embryos […] Their orientation suggests that they were born tail-first […] to reduce the possibility of drowning, an adaptation shared with other other highly aquatic amniotes” M.W. Caldwell & M.S.Y. Lee (2001) Proceedings of the Royal Society of London B, vol. 268, p.2397

  30. Viviparity in ichthyosaurs
    “For me, the fossil is a transporting piece of evidence. It shows a female ichthyosaur that died late in pregnancy or perhaps while giving birth; the baby was entombed with its mother in the mud.” J. Rennie (2000) Scientific American, vol. 283(6), p.8

  31. Viviparity in lizards, snakes and mammals
    “In over 100 lineages of […] squamates, the oviduct has been recruited for viviparous gestation of the embryos, representing a degree of evolutionary convergence that is unparalleled in vertebrate history.” D. G. Blackburn (1998) Journal of Experimental Zoology, vol.282, p.560

  32. Trichromatic vision in mammals
    Who has not enjoyed the splash of colour in a market: gorgeous red peppers, the green of basil and what on earth are these purple vegetables over there? All thanks to trichromatic vision, another story of convergence.

  33. Olfaction: insights into convergence
    Although olfaction is very widespread, there is abundant evidence for repeated convergence of key features, strongly suggesting that there really is an optimal solution to detecting smells.

  34. Venom in mammals (and other synapsids)
    Beware the venomous shrew! Yes, venomous. And convergent on some formidable lizards...

  35. Infrared detection in snakes
    Warm-blooded rodents watch out! There are heat-sensing predators on the prowl...

  36. Infrared detection in animals
    Some snakes are famous for 'seeing' infrared, but did you know that their heat-sensing abilities are rivalled by some beetles that can detect forest fires over considerable distances?

  37. Loss of olfactory capacity in primates and cetaceans
    It is widely thought that reduced olfactory capacity in apes is linked to the development of acute vision, especially trichromacy.

  38. Ancient opsins and vision in extinct animals
    Spectral tuning of the eye generally depends on key substitutions of amino acid sites in opsin proteins.

  39. Vision in echinoderms
    Among brittlestars and sea urchins we find visual systems that in some ways rival the arthropods in the form of compound eye-like structures.

  40. Lipocalins for milk and pheromone transport
    Lipocalins are proteins that bind to and transport small hydrophobic molecules such as lipids and steroids, and have been associated with biological processes such as milk production, pheromone transport and immune responses.

  41. Compound eyes in arthropods
    It is clear that amongst the arthropods as a whole the compound eye has evolved at least twice, and possibly even more times.

  42. Camera eyes in alciopid annelids
    There is a striking example in the group known as the alciopids, which are pelagic polychaetes. The similarity of their camera eye to the vertebrate eye has attracted considerable comment.

  43. Pinhole eyes in Nautilus and giant clam
    The pinhole eye has evolved not only in the Pearly Nautilus, but also in another group of molluscs, the bivalves and specifically the giant clams (Tridacna).

  44. Camera eyes in gastropod molluscs
    The fast-moving cephalopod molluscs are famous for their camera eyes, but why on earth have gastropod snails, which are not exactly known for their speed, evolved this superb visual organ at least four times?

  45. Telephoto eyes in animals
    Pursued by the paparazzi? Watch out for those animals equipped with telephoto lenses...

  46. Innate and adaptive immune systems
    A vile cough, soaring temperature? When attacked by nasty microbes, our immune system comes in handy. Surprisingly (or not), plants have come up with a very similar solution to dealing with pathogens, but independently...    

  47. Adhesive pads: from geckos to spiders
    In terms of adhesive pads we find they have a remarkably wide distribution evolving in at least four distinct groups, including members of the reptiles, amphibians, arthropods and mammals, with tentative parallels in sea urchins.

  48. Lysozyme
    Lysozymes are common antibacterial enzymes that protect our eyes and nose from infection, but some animals have recruited them for a rather different purpose...

  49. Gut fermentation in herbivorous animals
    Ever tried eating a newspaper? Don't. Plant cell walls contain cellulose, which is notoriously difficult to digest. Considering that all vertebrates lack the enzymes to attack this polysaccharide, how do so many of them manage to survive on a plant diet?

  50. Sleep in animals
    Suffering from insomnia? Fruit flies do as well...

  51. Woodpeckers and woodpecker-like birds and mammals
    You think woodpeckers are unique? Consider the ovenbirds. Or even the curious aye-aye.

  52. Swimming and thermoregulation in sharks and tuna
    Thunniform swimming depends on a large, lunate tail that is joined to the rest of the body via a narrow peduncle. Whilst the tail flicks backwards and forwards, so propelling the animal, the rest of the body hardly moves sideways.

  53. Developmental genetic pathways to convergence
    At first sight there is a fairly simple dichotomy between convergent features that have effectively the same genetic basis, and those where the same feature emerges but the underlying genetics are different. The former, however, is somewhat more complicated...

  54. Crustaceans: insights into convergence
    Whilst predominantly marine, quite a number of crustaceans have invaded freshwater habitats and even more interestingly a few demonstrate terrestrialization, effectively freeing themselves from their aquatic ancestry.

  55. Haemocyanin in arthropods and molluscs
    The degree of similarity between the active sites in arthropod and molluscan haemocyanin has been called “remarkable” and “startling”, but actually suggests that wherever in the universe life employs copper for aerobic respiration it will call upon haemocyanin.

  56. Elastic proteins
    What do rubber bands and fleas have in common?

  57. Crystallins: eye lens proteins
    Whereas typically technology demands furnaces, so that the glass for a lens is produced at hundreds of degrees Celsius and then requires most careful grinding, so nature calls upon proteins known as crystallins.

  58. Transparent tissues: eyes, bodies and reflective surfaces
    Read on if you want to know about the numerous animal equivalents to the invisible man...

  59. “Colour vision” in Firefly squid
    The Japanese firefly squid (Watasenia scintillans), which inhabits the deep ocean, has three visual pigments located in different parts of the retina that are likely to allow colour discrimination as they each have distinct spectral sensitivities.

  60. Penis form in mammals, turtles, birds and octopus
    The specific case of a penis with a hydrostatic structure, as well as an array of collagen fibres that allows both expansion and guards against aneurysms, has evolved in a strikingly convergent fashion in mammals and turtles.

  61. Frogs with fangs
    Teeth have clearly evolved a number of times, and one of the more interesting curiosities is found in the amphibians, notably in the frogs where several groups have independently evolved fangs.

  62. Electroreception in fish, amphibians and monotremes
    From an evolutionary point of view, electroreception is particularly intriguing as a sense modality that has been repeatedly lost and reinvented again.

  63. Octopus arm function
    If you want to see a truly remarkable example of convergence, then present an octopus with a piece of food and have a high-speed camera ready…

  64. Camera eyes of cephalopods
    The remarkable similarity between the camera eyes of cephalopods and vertebrates is one of the best-known examples of evolutionary convergence.