WASPS' COLOUR SENSE

Dominion, Volume 12, Issue 221, 12 June 1919, Page 5

WASPS' COLOUR SENSE

PREFERENCE FOB YELLOW AND ; ' BLACK. . Some interesting results of investigations into the habits of wasps have 'been; given by. Dr. Harold Wager before tho Jjinnean Society in a lecture on "Tht> Colour Sense of.Wasns." Dr. Wager made his experiments byobserving .wasps flying.towards and settling upon pieces of sugar plaoed upon sheets .of coloured paper. The expen- ■ niente show that in seeking their food waeps (Vespa .vulgaris) are guided by , their social instinct, their remembrance of locality,' and their power to' distinguish conspicuous colours or colour-con, trasts. They aro probably also guideo oy smell, but no experiments were made w test this. . • ..• • ■ ■ ■Under the conditions of the experiments waeps were attracted bf the strong colour-contrasts of white sugar on yellow, red, or black paper, and less strongly by the weaker colour-contrasts of vrlilt* sugar on blue or white paper. They showed very little discrimination among the various colours, but, so far as could be judged, when they hod a more or less free choice, untrammelled by their stronger instincts, they.flew to the colpurs in tho following' order: yellow, - black, red, blue, white, The wasps in the experiments showed ,a very pronounced tendency to come back 'always to the exact place where they had previously obtained sugar, irrespective of any colour that might happen to be there. When the sugar was removed only a short distance away they were much • puzzled, and only after flying about for some time were they able to discover it in its new place. Their social instincts were clearly indicated by the fact that they were always more strongly ■ attracted by other wisps than by place or colour. This attraction for other wasps was so strong that they would frequently fly at first to a piece of sugar surrounded by. dead wasps in preference to other pieces of etigar in the immediate neighbourhood which wero free of wasps. They very larely settled, however, on\a piece o'i sugar surrounded by dead wasps.