Two, and four supplementary, chicks of the Grey Staring, Sturnus cineraceus, were handraised under close observation. The occurrence and development of their behaviours were carefully noted and over 50 kinds of behaviour and vocalization were recorded as classified in the introduction, and 34 of which were listed in Fig. 8, showing the days of occurrence after hatching. The ontogenetic analysis by behaviour system was made based on Kortlandt's method as shown in Figs. 3-7. Each behaviour was named and described in the text which are summarized as follows: Without external stimulation, the gaping of early chicks (5-7 days) was gradually induced by hunger, 20 minutes after being fed 1g. of food, and advanced from: bill up-pointing → yawning → neck-stretching to gaping. Any sound, the door-closing, dog-bark, badgerigers' voice, became the stimulus for gaping. Touching the nest caused freezing but also gaping in hungry condition. The strong bursting sound caused freezing. Rising temperature induced, and decreasing one suppressed the gaping impulse. At least by 12th day, the chicks had been imprinted by the author's voice and not reacted to high-pitch sounds. This was confirmed also after they were fledged. Eyes opened on the 10th day but directed gaping was first noticed on the 13th day. The sight was best at 1-60cm., reacting also at 1m. and weakly at 2.5m. However, the lateral sight did not developed until the 15th day, when the hostile behaviours became developed. The pecking action first appeared on the 13th day as a weak impulse with the upward-pointed bill in the absence of real object to peck, but they also pecked the tip of forcets 1cm. before the bill. Eating of food after such a peck and the mutual pecking of the bill were noticed from 13-15th days. After the 20th day, the tongue-tip tasting particularly of small black particles became frequent. They liked to taste the sugar but hated the salt. The fledged young did not eat by themselves the pasted food in the container until at least 35th and 37th days, two weeks after leaving the nest. Vomitting the stones of fruits (and hard objects) given by parents is an important physiology in the chicks. The cherry stones are vomitted about 1.20h. (once 50min.) after intake. Also in fledged young which may often eat inedible substance, the vomitting is of survival value (observed). The food-refusing was observed on the 13th day and the humility behaviour with False begging was noticed on the 17th day. The Bill-opening, characteristic to the starlings, occurred on the 18th day as a weak innate impulse in the absence of definite object (there was a little cotton). From about the 20th day, various use of bill became developed (see list in the text) and the Bill-rubbing (or cleaning) behaviour was first noticed. The foraging of fledged young is very inefficient, being much interested in shaking the feather, string or fallen leaves (a long string was half swallowed!) and could find little real food. When the water was given on the 22nd day, they first pecked at it and then real drinking followed. Beside scooping the water, they also can suck it, with the vertically inserted bill (from the perch above the water). Bathing was willingly done on the 26th and 22nd, but not 21st (same bird), day when they were first given water. Panting in both naked chicks and fledged young was induced at 30°C (or 29°C) by heating them with electric light or in natural summer temperature, and the breathing increased to 26times/15sec. in 15 day solds, which breathed 14times/15sec. at 26°C. The Lateral heat (or Sun) bathing could be at once induced in 22 days olds by 60 wat electric light, but after a while panting occurred (perhaps at over 30°C). The Back heat-bathing was reflectively performed when the bird was brought out to the sunshine.
1. The laying season is from April to July, with the peak from late April to mid May. The eggs are laid between 4.30-7.00 a.m. 2. The clutch size varies 3-7, with the mean 4.98 and is larger in the first clutch. 3. The length varied 17.0-24.5 (mean 19.6) mm, with the σ 0.81mm. 4. The bredth varied 11.8-16.6 (mean 14.1) mm, with the σ 0.65mm. 5. The shape index varied 62.1-87.0 (mean 71.4) mm. 6. The size index varied 224-375 (mean 270). 7. The weight varied 1.5-2.0 (mean 1.8) g. 8. The volume index varied 0.59-0.76 (mean 0.69). 9. The variations within clutch are smaller than those by clutch. 10. The variation is larger in the first than the second clutch Seasonally, largest in mid May. 11. The negative correlation exists between the length and shape index. Other correlations were all positive.
Sleeping and roosting in the Grey Starling may be two quite different behaviours from the point of view of ethology. The sleeping appetite is of entirely physiological one. The roosting, on the other hand, is a series of behaviours, commenced while the starlings are on the feeding ground. Feeding in the open field, the starlings defend themselves against the predators by joining into a flock. Towards the evening, the anxiety caused by lowering light intensity may stimulate the appetite for mutual dependence which releases their flocking behaviour in form of joint feeding and pre-roosting flight assembly. Then, still lowered light intensity may cause the next appetite to arise, the appetite for taking shelter, which releases the roosting flight towards the roost (or shelter). Arriving at the roost, they make a pre-roosting assembly and by gradual loss of light intensity (to almost O Lux), their final appetite for entering in shelter may be evoked. After this, an entirely physiological impulse to sleep may be activated. These postulated roosting procedure is diagrammatically shown.
The stomach stones found packed in the proventriculus of two young Adelie Penguins, brought from Japanese "Showa" Antarctic Base, are reported. The number and species of stones contained in proventriculus A were 26 Biotite Gneiss pieces, 6 Aphite pieces and 1 small Feldspar, with some tiny pebbles and B contained 25 Biotite Gneiss, 13 Aphite and 1 Amphipolite, with some small peblles (Table 2). The larger stones were size of finger head, weighing more than 1gr. to even 5.9gr. (Table 1), and their total weights were 54gr. (A) and 21.5gr. (B). Such stones in the proventriculus are not same functionally as usual stomach stones found in the gizzard of other birds. Judging from literture on the Emperor Penguin, they were apparently fed by parent and the function of giving weight for deep diving may not be rejected at once until other function becomes clear.
The comprehensive species concept considered from ornithological point of view in the previous paper (Misc. Rep. Yam. Inst. nos. 15, 16) was further summarized for a synposium of Zoological Society held in October, 1961. The seven approaches for species analysis may be classified, i. e., 1. Phenotypic or Morphological, 2. Anatomical or Functional, 3. Physiological or Biological, 4. Genotypic or Molecular, 5. Ethological or Behavioral, 6. Populational or Sociological and 7. Supplementary. These approaches are on the levels of subindividual, individual and superindividual. Throughout these levels the adaptations of all kinds, endo-, exo- and socio-adaptations, are universal. These considerations leads to a comprehensive species concept diagrammatically expressed here.