Vibrational communication in mammals
Kangaroo rats drum their foot on the ground upon encountering a snake. Why? Read on for this and many other fascinating examples of vibrational communication in mammals…

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?

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...

Wire plants, moas and elephant birds
Madagascar and New Zealand were once home to giant herbivorous birds. And the plants have not forgotten...    

Parthenogenesis in Australian lizards and insects
“Evidence on the origin and spread of the two best-studied cases of parthenogenesis from the Australian arid zone, the grasshopper Warramaba virgo and the gecko Heteronotia binoei, suggests that they evolved in parallel.” – Kearney et al. (2006) Molecular Ecology vol. 15, p.1743

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.

Thanatosis (feigning death) in spiders and insects
Beetles that "play possum"? A rather interesting example of convergence…

Xylem vessels in vascular plants
Vessels are characteristic of the angiosperms, and yet they have evolved independently in several other groups, including the lycophyte Selaginella, horse-tail Equisetum and the enigmatic Gnetales.

Torus-margo pits in vascular plant xylem
Torus-margo pits probably evolved once in the gymnosperms, after the split of more advanced gymnosperms from the cycads. Surprisingly, eight genera from five families of angiosperms, which are characterised by highly effective xylem vessels, have also evolved torus-margo structures.

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

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

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...

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

Secondary xylem (wood) in vascular plants
Evolution of wood in plants as distantly related as lignophytes, Calamites and Lepidodendron is an elegant example of convergent evolution. Plants responded in a similar way to a need for better structural support as they diversified and increased in size.

Xylem vessels in vascular plants
Vessels are characteristic of the angiosperms, and yet they have evolved independently in several other groups, including the lycophyte Selaginella, horse-tail Equisetum and the enigmatic Gnetales.

Malodorous flowering plants
Several groups of angiosperms have flower structures that produce foul odours to attract pollinating insects. This strategy is convergent, being found in species as distantly related as the 'Titan arum' Amorphophallus titanium (a monocot) and the 'Corpse flower' Rafflesia (a eudicot).

Explosive discharge in fungi and plants
The very rapid release of reproductive bodies is perhaps most famous in the fungi, where several methods of flinging spores at high velocity have evolved independently.

Dental batteries in ceratopsians, hadrosaurs and elephants
The dental batteries or 'pavements' of ceratopsians and hadrosaurs evolved independently, and yet the dentition of several more distantly related animals also converges on their highly adapted tooth form.

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.

Desert plants with succulent leaves
Perhaps the most striking case of convergence among leaf succulents occurs between Agave and its relatives Yucca and Hesperaloe in the Americas and Aloe and its relatives (e.g. Haworthia and Gasteria) in Africa.

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.

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.

Wire plants, moas and elephant birds
Madagascar and New Zealand were once home to giant herbivorous birds. And the plants have not forgotten...    

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.

Cavitation: bubble formation in plants, reptiles and shrimps
The formation of bubbles in a fluid is known as cavitation. Typically this occurs at low pressures, and is perhaps best known in the xylem of plants where embolisms can be destructive to the surrounding tissues.

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…

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.

Ants: insights into convergence
Trap-jaws, silk and agriculture – just a few examples of convergence in the arguably most successful group of insects, the ants…

Snail eating: an asymmetric diet
Snails may not be everyone's first choice on the menu but several distinct colubrid snakes have evolved expert techniques for gorging on these nutritious gastropods.

Vibrational communication in mammals
Kangaroo rats drum their foot on the ground upon encountering a snake. Why? Read on for this and many other fascinating examples of vibrational communication in mammals…

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…

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...

Foregut fermentation in birds
A foregut-fermenting bird was long considered a paradox. But what about the hoatzin, a curious South American bird known locally as the "stinking pheasant" thanks to its smell of fresh cow manure?

Monochromacy in mammals
Underwater environments are dominated by blue light. Ironically, whales and seals cannot see blue, because they have independently lost their short-wavelength opsins.

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...

Agriculture in wood wasps
The most famous hymenopteran farmers are, without doubt, the attine ants. Rightly so, but they are not the only ones...

Agriculture in dugongs
When you think of grazing mammals, you might envisage large herds of antelopes roaming African savannahs. Did you know that there is an equivalent in the ocean, feeding on seagrass?

Agriculture in gall midges (Diptera)
Flies, fungi, farming - sounds interesting? Read on if you want to learn about some rather different gall midges...

Agriculture in beetles
Think of weevils and most likely you'll think of spoiled food. But some weevils have turned to farming...

Agriculture in aquatic snails
Termites and ants are famous for tending fungal gardens, but did you know that also a marine snail farms a fungus? And this is not the only example of agriculture in this group…

Agriculture in damselfish
Don’t be tempted to think human agriculture is unique. On many coral rocks, there are very similar things going on…

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

Torus-margo pits in vascular plant xylem
Torus-margo pits probably evolved once in the gymnosperms, after the split of more advanced gymnosperms from the cycads. Surprisingly, eight genera from five families of angiosperms, which are characterised by highly effective xylem vessels, have also evolved torus-margo structures.

Reversion from xylem vessels to tracheids
In three plant taxa that evolved in environments with frequent freeze-thaw cycles (Winteraceae, Trochodendraceae and cold desert Ephedra), vessel evolution has been reversed independently in favour of a return to a tracheid-based vascular system.

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...

Mitochondrial genome convergences
Most likely, mitochondria have a single evolutionary origin, but that doesn't mean they are immune to convergence...

Evolution of birds from feathered reptiles
Birds, in the sense of flying descendants of feathered reptiles (a more expansive group than the "true" birds in today's skies), evolved several times from within the theropods.

Mimicry in fungi
Insects pollinating flowers are a familiar sight. But what happens when the "flower" is actually a fungus? Still "pollination", but now it is fungal spores. Read on to learn more about the fungi that mimic flowers...

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.

Mushrooms and their relatives (Basidiomycota)
Mushrooms are not only tasty, but also provide numerous examples of evolutionary convergence...

Reptile dentition: convergence on complex occlusion
Some reptiles have transverse chisel-like teeth for slicing, and others have teeth bearing projections ('cusps') that interlock and slice or grind tough food. In each case evolutionary parallels are clear both within and outside the reptiles.

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.

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.

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

Carnivorous fungi: a diet of worms (and other animals)
Fungi have learnt how to trap living prey, notably nematodes but also a range of other animals include rotifers, tardigrades and even springtails.

Ascomycete fungi: insights into convergence
Today ascomycetes are an extremely important group of fungi, and they take their name from the reproductive structures known as ascii.

Thanatosis (feigning death) in spiders and insects
Beetles that "play possum"? A rather interesting example of convergence…

Dandruff, Malassezia and Candida
The presence of Malassezia does not guarantee dandruff, as this fungus is commonly present on healthy skin, but it evidently central to dandruff production if other key factors support it.

Gliding in Draco lizards and tree snakes
“The agamid lizard genus Draco (consisting of the so-called ‘flying dragons’) exhibits an array of morphological traits associated with gliding.” – A.P. Russell & L.D. Dijkstra (2001) Journal of the Zoological Society of London, vol. 253, page 457

Gliding mammals
Gliding mammals rely primarily on extensive skin membranes or ‘patagia’ that stretch between fore- and hind-limbs, creating a wing-like structure.

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.

Ecological adaptations in Moloch and Phrynosoma lizards
Lizards of the genera Phrynosoma and Moloch have been considered a classic example of convergent evolution J. J. Meyers & A. Herrel (2005) The Journal of Experimental Biology, vol. 208, p. 114

Drinking adaptations in desert lizards
Both Moloch horridus and [...] Phrynosoma cornutum have the remarkable ability to transport water over their skin’s surface to the mouth where drinking occurs. Sherbrooke et al. (2007) Zoomorphology, vol. 126, p. 89

Parthenogenesis in Australian lizards and insects
“Evidence on the origin and spread of the two best-studied cases of parthenogenesis from the Australian arid zone, the grasshopper Warramaba virgo and the gecko Heteronotia binoei, suggests that they evolved in parallel.” – Kearney et al. (2006) Molecular Ecology vol. 15, p.1743

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.

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

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

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.

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...    

Silk production and use in arthropods
Remarkably, fossil silk is known, especially from amber of Cretaceous age. Material includes both silk with trapped insects, possibly from an orb-web, and strands with the characteristic viscid droplets that are the key in trapping prey.

Biological uses of silk: from webs to ballooning
What material is so versatile that it can be used for capturing prey, building nests, communication and even cleaning? The answer: that most remarkable of biomaterials - silk.

Bacterial carboxysomes (and other microcompartments)
It is now clear that the cellular construction of at least the eubacteria is more complex than realized, and includes organelle-like structures known as microcompartments, of which the best known are the carboxysomes.

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...

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.

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?

Sap feeding and honey-dew production in insects
Interestingly, it has now been shown that the saliva of the aphids has an analogue to the anti-coagulant properties of blood suckers, subverting the wound repair mechanism of the plant.

Dolphin communication, cognition and sociality
Dolphins are one of the most intriguing sources of evolutionary convergence, having cognitive abilities that seem to find many parallels in the great apes, and rather remarkably even extend to tool use.

Strepsipterans: convergent halteres and eyes
Strepsipteran females spend their whole life inside a wasp. The males are rather more exciting, particularly in terms of convergence…

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

Zinc in teeth
On land, we find the employment of zinc to reinforce feeding structures in the fangs of spiders, and also in a variety of insect groups.

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.

Hummingbirds and hummingbirdoid moths
Like other birds hummingbirds are warm-blooded, but so independently are the hawk-moths, which like a number of insects have evolved thermoregulation.

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...

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.

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.

Defence in frogs: toxins and camouflage
The many striking examples of convergence most famously include the case of mimicry, but the question of defence also extends to the use of toxins (and venoms), such as alkaloids, where we also find molecular convergence.