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Tongues of chameleons and amphibians
Convergence in tongue function represents repeated morphological exploration within different lineages made possible by loss of an ancestral functional constraint -
Agriculture in gall midges (Diptera)
Flies, fungi, farming - sounds interesting? Read on if you want to learn about some rather different gall midges... -
Mitochondrial genome convergences
Most likely, mitochondria have a single evolutionary origin, but that doesn't mean they are immune to convergence... -
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. -
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? -
Mammal-like placentation in skinks (and fish)
“Only two types of vertebrates [have] evolved a reproductive pattern in which the chorioallantoic placenta provides the nutrients for fetal development. One is [...] the eutherian mammals […], and the other, a few lineages of the family Scincidae.” A.F. Flemming (2003) J Exp Zool 299A 33-47 -
Baculum (penile bone) in mammals
Ouch!! Gentlemen, fancy a bone in your penis? Seems a bit risky, given it could fracture during copulation. Even our near ancestors had such a bone. It has probably evolved several times, but what is its function? -
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. -
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 -
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... -
Agriculture in beetles
Think of weevils and most likely you'll think of spoiled food. But some weevils have turned to farming... -
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... -
Intelligence and cognition in birds
House sparrows are known to gain access to shopping malls by flying in front of sensors that operate sliding doors, whilst herons have been shown to be adept fishers using baits and lures. -
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... -
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. -
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... -
Tool use in birds
What animals can drop stones into a water-filled tube to bring floating food within reach, bend wire to form a hook and use a short stick to retrieve a longer one that allows them to fish for food? Obviously chimpanzees? No, New Caledonian crows have evolved sophisticated tool use independently. -
Hummingbirds, sunbirds and honeyeaters
One of the most well known examples of convergence among birds is between hummingbirds, sunbirds and honeyeaters, all of which are small, dominantly nectar-feeding birds. -
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. -
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… -
Nuptial gifts in insects and spiders
Male dance flies lure females with a dead insect. Not very romantic, you might think, but it certainly does the trick. Hence, such nuptial gifts have evolved in numerous other arthropods... -
Agriculture in wood wasps
The most famous hymenopteran farmers are, without doubt, the attine ants. Rightly so, but they are not the only ones... -
Scanning eyes in molluscs and arthropods
Some sea snails have a linear retina. What a hopeless arrangement, to see the world through just a narrow slit! Not quite, because they have come up with a rather intriguing trick to extend their visual field - and it's a trick too good to use only once. -
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... -
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... -
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. -
Worm-like body form
Man is but a worm, but so are many other vertebrates... -
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? -
Agriculture in ants: leaf-cutters (attines) and non-attines
In some species, special squads leave the nest early each day, ascend the tree-trunks and then spend hours cutting out pieces of leaf that are dropped to other units on the ground. -
Brood parasitism in cuckoos and other birds
Obligate brood parasitism has evolved several times independently in birds. Apart from the cuckoos, it can be found in four other, only distantly related families. -
Agriculture: from ants to dugongs
Human farmers tending their fields are a familiar sight. But don't forget about those fungus-farming termites or the fish with a garden of algae… -
Dicyemids and chromidinids: enigmatic endoparasites
Dicyemids and chromidinids are tiny, worm-like or 'vermiform' creatures that typically live inside the kidneys ('renal organs') of cephalopod molluscs such as octopus, squid and cuttlefish. -
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. -
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. -
Desert plants with succulent stems
Fleshy, succulent stems have evolved in several distantly related desert plant families, including cacti, certain species of Euphorbia and two genera of the family Asclepiadaceae, Hoodia and Stapelia. -
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 -
Foregut fermentation in mammals
Foregut fermentation is best known from the ruminants, such as cattle, deer and giraffes, that regurgitate and rechew their food to aid microbial digestion. However, they are not the only mammals to have evolved this digestive strategy... -
Autumn leaf colouration
Autumn colours are likely to be adaptive, as the 'default' is simply to remain green up to leaf fall, and both red and yellow leaf colouration have evolved independently on many occasions in gymnosperms and woody angiosperms. -
Beetles: insights into convergence
The beetles are probably the most diverse animal group on earth, so it is not at all surprising that they provide many fascinating insights into convergence. -
Carnivorous plants
All plants are harmless? Well, not quite - at least not when you're an insect... -
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. -
Succulent desert plants
Classic examples of convergence in desert plants include the so-called 'stem succulent' cacti in the Americas and cactus-like Euphorbia species in Africa and South Asia, and also the striking similarity between 'leaf succulent' Agave and Yucca of the Americas and Aloe and its close relatives in Africa.
