Leading Article: You never see a pigeon buy a ticket

ANOTHER crushing blow for Thomas Aquinas and the rest of the human supremacists. Pigeons, it is becoming clear, thanks to a round of learned correspondence in New Scientist, have learnt how to take Underground trains. Not for them the flapping effort of flying round London; they now hop on at, say, Cockfosters, and alight at Ravenscourt Park, having changed at South Kensington. We can only marvel at this extension of the homing instinct, while also marvelling at those agitated people who continually accost us beneath the indicator boards next to the maps on the Northern Line demanding to know if they are "right for Bank". At the same time, though, it is hard not to feel a little resentful; for if pigeons are smart enough to read the maps, they must be smart enough to buy a ticket, too.

But subhuman triumphalism was all around us last week. On Wednesday, we had to endure endless heavily-humoured accounts of the return of the Downing Street cat, Humphrey, feared dead after an absence of three months, but discovered living happily half-a-mile away. Then, on Thursday, Chester the tortoise was found 35 years after he had disappeared from his home in Lyde, Herefordshire. He had, apparently, travelled 150 yards. Several thoughts ventured about these two remarkable happenings were, in our opinion, insufficiently aired. One was that Humphrey, rather in the manner of The Prisoner of Zenda, was not Humphrey at all, but a similar looking cat pressed into service to overshadow the other return, that of Baroness Thatcher to Downing Street for her 70th birthday celebrations. Another was that Chester had done rather better than anyone using a Railtrack timetable. Perhaps they should get pigeons to do the next one.