Talk to the Animals - 8pm, BBC1
At one point in this look at how animals communicate, presenter Lucy Cooke tells us “This is social networking, mongoose-style!” And we then see the mongooses’ squeaks and grunts translated on screen with hashtag captions like #lisasearching and #johndigging and we wonder if they really needed to present wild mammals as if they were on Twitter.
Probably not, but it makes the point that some animals constantly network, in the case of mongooses with a cacophony of calls that bond the family group together and keep everyone in the loop. Hippos do something similar, we discover, while chimps have at least 30 different calls and 66 different gestures: a chimp dictionary is well on the way.
Operation Cloud Lab: Secrets of the Skies - 8pm, BBC2
Apparently, when water vapour condenses into clouds, it releases latent heat energy, which then helps to keep the cloud afloat and drives weather systems. And yes, that sentence may have been enough to make some of you drift into a cloudy reverie: I don’t entirely understand it myself and I’ve watched the documentary.
But never mind: we see Andy Torbet parachute through a cloud to prove it, and we’re told in no uncertain terms that a large cloud can generate heat energy equivalent to a nuclear warhead. A nuclear warhead!
That’s the kind of well-blow-me-down fact we want from our science docs and this one has enough of them, mostly delivered by peerless voiceover man Steven Mackintosh. Meanwhile, we watch a group of scientists on an airship do experiments. It could be dull, but it isn’t at all.
The Fifteen Billion Pound Railway - 9pm, BBC2
The graphics in this series about Crossrail are wonderful. Slick animated diagrams show how tunnels for London’s new underground line have to weave between existing bits of the network.
At one stage engineers talk about “the eye of the needle” at Tottenham Court Road: the 900-ton digging machine has to bore its way through a gap between the Northern Line and an escalator shaft with less than a metre’s leeway either side.
“It’s like conducting open-heart surgery while the patient is still awake,” says one of the project managers. The drama here occasionally flags (watching cranes craning is only so interesting) but it makes you appreciate the ingenuity of the engineering.
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