Counting with Colours? Effect of Colours on the Numerical Abilities of House Crows (Corvus splendens) and Common Myna (Acridotheres tristis).
We conducted several aviary experiments to investigate the influence of colours in quantity judgments of two species of birds; house crow (Corvus splendens) and common myna (Acridotheres tristis). Different quantity (in seven different food proportions) of mealworms were presented nonsequentially to all birds using artificially coloured red mealworms, for experiment 1, and using artificially coloured green mealworms, for experiment 2. Both red and green coloured mealworms have no significant effect on house crow's quantity judgments (red:
F6,30 = 1.748, p = 0.144; and green:
F6,30= 1.085, p = 0.394). Common myna, however, showed a strong influence of red colour in their quantity judgment (
F6,30 = 2.922, p = 0.023) as they succeeded in choosing the largest amount of food between two cups, but not when offered food using green coloured mealworms (
F6,30 = 1.183, p = 0.342). In the next experiment, we hypothesised that both house crow and common myna will prefer red coloured food items over green coloured food items, when factors such as the amount of food is equal. We chose to test red and green colours because both colours play an important role in most avian food selections. Results showed that there were no significant differences in the selection of red or green coloured mealworms for both house crows (
F6,30 = 2.310, p = 0.06) and common myna (
F6,30 = 0.823, p = 0.561).
School of Biological Sciences, Universiti Sains Malaysia, 11800 USM, Pulau Pinang, Malaysia.
Nor Amira Abdul
NA
Rahman
School of Mathematical Sciences, Universiti Sains Malaysia, 11800 USM, Pulau Pinang, Malaysia.
Zalila
Z
Ali
School of Biological Sciences, Universiti Sains Malaysia, 11800 USM, Pulau Pinang, Malaysia.
Wan Fatma
WF
Zuharah
School of Biological Sciences, Universiti Sains Malaysia, 11800 USM, Pulau Pinang, Malaysia; Centre for Marine and Coastal Studies (CEMACS), Universiti Sains Malaysia, 11800 USM, Pulau Pinang, Malaysia.
Nik
N
Fadzly
Birds; Colours; Common Myna; Crows; Numerical Abilities
Proc Biol Sci. 2008 Oct 22;275(1649):2373-9
18611847
J Exp Biol. 2004 Jun;207(Pt 14):2465-70
15184518
Science. 2011 Dec 23;334(6063):1664
22194568
J Exp Psychol Learn Mem Cogn. 2002 May;28(3):509-20
12018503
J Vis. 2010 Jun 01;10(6):20
20884569
Behav Processes. 2011 Jan;86(1):109-18
20971169
Science. 2004 Dec 10;306(5703):1903-7
15591194
Vision Res. 2000;40(16):2187-200
10878280
Proc Biol Sci. 2004 Jul 22;271(1547):1435-42
15306314
PLoS One. 2012;7(5):e38145
22693591
Nat Rev Neurosci. 2003 Jul;4(7):563-72
12838331
Science. 1980 Nov 28;210(4473):1033-5
7434014
Trop Life Sci Res. 2014 Aug;25(1):95-103
25210590
Psychol Sci. 2002 Mar;13(2):150-6
11933999
J Gerontol B Psychol Sci Soc Sci. 2007 Nov;62(6):P305-12
18079414
Anim Cogn. 2006 Oct;9(4):377-91
16909236
Curr Biol. 2008 Mar 25;18(6):425-8
18342507
Psychol Sci. 2004 Nov;15(11):776-81
15482450
Nature. 1992 Aug 27;358(6389):749-50
1508269
J Vis. 2009 May 15;9(5):14.1-16
19757892