Q & A
Email your questions to wildquestions@immediate.co.uk
Does the UK have any coral reefs?
HELEN SCALES ANSWERS:
Corals are certainly not confined to the shallow, sunny waters of the tropics. More than half of around 5,000 known species of corals live in cold and deep waters. The main reef-forming coral in UK waters is a bushy, white species, Lophelia pertusa, or Desmophyllum pertusa as some scientists prefer to call it.
Mostly located off the west coast of Scotland, Lopheliareefs are found from around 150m deep and are very slow growing. A huge reef off the coasts of Barra and Mingulay in the Outer Hebrides covers more than 100km2. In the Rockall Trough, 160km north-west of Scotland’s Cape Wrath, the Darwin Mounds are thickets of Lophelia, as well as another species Madrepora oculata.
Similar to tropical reefs, coldwater reefs form important habitats for many fish and have been heavily targeted by deep-sea trawlers. Darwin Mounds were badly damaged before they were protected in 2004.
Are birds smelly?
DAVID LINDO REPLIES:
We don’t think of birds as smelly, not in the same way that dogs have a characteristic smell, for example. But ask any bird ringer and they will tell you that their mist nests and bird bags have a particular ‘birdy’ smell that could be loosely describe as like bitter, stale perfume. This smell may emanate from feather dust and the oily secretions from the birds’ preen glands, which they use to protect and waterproof their plumage. Odours are particularly strong in seabirds. Storm petrels famously have a mustiness detectable at close quarters, and manx shearwaters are also pretty niffy.
Further afield, the anis, relatives of the cuckoos, particularly pong. As adults they have few enemies – presumably their whiff must be off-putting.
Finally, the skin of certain pitohui species, which hail from Papua New Guinea, contain powerful neurotoxic alkaloids that are believed to serve as a chemical defence against ectoparasites or predators like snakes and even humans. Indeed, Papua New Guineans call them ‘rubbish birds’ due to their toxicity rendering them inedible.
Why are there so many species of dandelion?
JOSHUA STYLES ANSWERS:
We’re all familiar with dandelions, but did you know that here in Britain we have around 250 different species? From tiny ones scarcely bigger than a 50p piece to some that are spottier than a jaguar. But why and how do we have so many species?
The answer is a peculiar process known as ‘apomixis’, through which plants are able to reproduce by seeds without the need for pollination – aform of asexual reproduction. These seeds produced an exact clone copy of the parent. But how does apomixis mean we have so many different dandelions?
It all started millenia ago where the fertile ancestors of our dandelions in southern Europe interbred to create flowers that were fully apomictic. These hybrids then spread out over northern Europe to occupy all manner of different habitats where they may still be found today.
And because these peculiar hybrid plants were fixed, plant taxonomists have described each of these different dandelions as microspecies.
Where are marsupials found?
MEGAN SHERSBY ANSWERS:
Distinctive for carrying their young in a pouch, marsupials are a group of mammals that most of us probably associate with Australasia and Wallacea, thanks to wellknown species such as kangaroos, koalas, Tasmanian devils, wombats and the now-extinct thylacine, also known as the Tasmanian tiger.
However, although roughly 70 per cent of extant marsupial species are found there, there are marsupials in the Americas too. The most famous is the Virginia opossum, North America’s only marsupial species, which spread northwards from South America in the Great American Interchange. ‘Opossum’ is derived from the Algonquian word ‘wapathemwa’, meaning ‘white animal’.
Do any non-human animals tend lawns?
STUART BLACKMAN ANSWERS:
There’s a theory that the considerable time and effort many humans put into maintaining a tidy lawn has its roots in our evolutionary past, when it might have been a good idea to keep the area around our homes free of tall vegetation so as to be able to see the approach of dangerous animals such as snakes. And we may not be the only animal species to do it. On the grasslands of China’s Inner Mongolia, Brandt’s voles chop down the tall, unpalatable brunchgrass for similar reasons – to increase the visibility of approaching predatory shrikes – giving them more time to take evasive action. The scientists also found that the grasses weren’t being taken down into the burrows, and when biologists excluded the shrikes from an area of vole habitat using netting, the rodents saved their energies and let the grasses grow. Meanwhile, the shrikes tend to avoid manicured habitat, apparently recognising it as poor hunting ground.
RECORD BREAKER!
What’s the world’s largest frog?
The world’s largest frog species is very aptly named – the goliath frog, or goliath bullfrog. It can grow up to 32cm in length and weigh up to 3.25kg. Despite its remarkable size, it doesn’t begin with a headstart. Instead, its tadpoles are the same size as an average frog tadpole. During a recent survey, the species was seen in Equatorial Guinea for the first time in almost two decades.
FACT.
Deemed as a harbinger of evil and death in Malagasy legend, the nocturnal aye-aye fills the same ecological niche as a woodpecker, feeding on insects and invertebrates within trees.
WHAT ON EARTH?
Pretty in pink
Japan has its cherry trees; the Himalayas have their rhododendrons; Scotland has its heather. But plants don’t come much pinker than these pink trumpet trees. The national tree of Paraguay – where it is also known as the pink lapacho – grows throughout much of Latin America, from northern Mexico to northern Argentina. This one was photographed by helicopter in Brazil’s Carajás National Forest, spotted amongst a sea of green. The name comes from the trumpet-like flowers, which burst into life in the southernhemisphere spring before the leaves appear. If ever a tree deserved a fanfare…
FAST ANSWERS
Are honey badgers actually badgers?
Also known as the ratel, the famously aggressive honey badger was once thought to be a type of badger species and so was grouped by scientists in the Melinae subfamily with species such as the European badger. However, it’s since been found to be more closely related to the martens, and is now placed within its own subfamily, Mellivorinae.
Where was the world’s first botanic garden?
The Orto botanico di Pisa was established in 1544 by the University of Pisa, making it the first botanic garden anywhere in the world. However, it was expanded and moved in 1563. The oldest to remain in tact and in place is the Orto botanico di Padova, set up a year later in the Venetian Republic town of Padova, now part of Italy.
Why do films dub bald eagle calls?
The iconic call of the bald eagle in movies and TV series is actually the dubbed scream of a red-tailed hawk. This is simply because the bald eagle doesn’t actually have an impressive call. Instead, it’s usually described by birders as more of a chuckle.
INSTANT EXPERT
Speciation: sources of biodiversity
EVOLUTIONARY HISTORY CAN BE represented by a tree of life on which extinction stops some branches from growing while speciation – the process that produces new species – maintains or increases nature’s diversity. And although Charles Darwin’s revolutionary book is titled On the Origin of Species, it doesn’t really explain how or why species might originate.
What is a species anyway?
It’s controversial. A species is a population of organisms whose members share common characteristics. But biologists don’t agree on one definition for what a species is. Plants and fungi are typically defined by features (morphology), for instance, whilst animal species are traditionally based on whether members interbreed to create fertile offspring – and species are now often distinguished by DNA.
Why does speciation occur?
Changes to an environment – triggered by factors such as climate, migration or interactions with other species – can reveal niches whose resources are ready to be exploited. Such ecological pressures or opportunities can drive a population to evolve into two potentially-distinct groups, or ‘incipient species’, if they each adapt to a niche through evolution by natural selection.
Once survival of the fittest has pushed incipient species to be specialised for their respective niches, any hybrids formed by interbreeding would be less well-adapted and less likely to survive, reinforcing divergence. This was suggested by Alfred Russel Wallace (who co-proposed the theory of natural selection) in his book Darwinism, and is now known as the Wallace effect.
So what prevents interbreeding?
If members from two incipient species keep combining genetic material and make offspring, they share a gene pool and may not diverge into distinct populations. That outcome is prevented when a pair of sister species accumulate differences in physiology or behaviour that create reproductive barriers that block any gene flow between the two species before or after a zygote (fertilised egg) develops – in organisms with sexual reproduction, known as pre-zygotic or post-zygotic isolation.
Post-zygotic barriers don’t prevent mating but a hybrid might be infertile, for instance, whereas pre-zygotic barriers include signals such as a courtship song or dance that’s essential for recognising compatible mates. Even organisms that can’t move or choose partners directly have barriers that block interbreeding: in flowering plants, for example, orchid species might look identical but have subtle distinctions to attract certain pollinators.
How do new species originate?
There are two main routes. Allopatric speciation occurs when sister species inhabit non-overlapping geographic ranges, after a structure – like a river or frozen water – physically separates members of a population or lets individuals migrate to new locations. The most famous example is Darwin’s finches, 13 species scattered across the Galápagos archipelago that show striking variation in size and shape, from the small tree finch that uses its curved beak to extract insects, to the large ground finch that uses a strong beak to crack open nuts and seeds. Genetic analysis suggests the finches are descended from songbirds called grassquits that hopped onto the Galápagos islands from mainland South America using a glacier during the last ice age.
The other route to speciation, known as sympatric, occurs when sister species live together (and presumably emerged) in overlapping geographic ranges. This process, sympatric speciation, seems less common across the tree of life but is also the dominant route in certain groups: in the African Great Lakes, cichlid fish evolved into thousands of species by colonising micro-habitats at various depths.
Which organisms contribute most to biodiversity?
Symbiotic bacteria will be geographically separated if they live in hosts that become new species. Because an estimated 79 per cent of speciation events occur in those endosymbiotic bacteria – which make up most living things – and most animals are insects, the majority of Earth’s biodiversity is probably generated by microbes and their insect hosts.
BBC WILDLIFE EXPERTS
