LAUGHING Doves in the LAB 17
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Vol. 21, No. I LAUGHING DovEs IN THE LAB 17 Laughing Doves in the Lab W. F. HOLLANDER Genetics Department,Iowa State College, Ames, Iowa Downloaded from http://online.ucpress.edu/abt/article-pdf/21/1/17/15565/4439058.pdf by guest on 28 September 2021 The "blond" color variety, typical of the domestic h . i . .o ; A pigmen. ring neck or laughing dove. Female specimen. The "white" variety- actually not devoid of pigment. Students when asked what kind of bird will be males, wvhileembryos with pink eyes laughs are likely to respond "hyena," or "par- will be white females. rot," or "laughing jackass," or even "Woody To explain this feat, one assumes that the Woodpecker." Few are acquainted with the color genes are borne on the sex chromosomes. domestic dove, part of whose repertoire is a Studies of the dove's chromosomes"' indicate laugh which very possibly inspired Woody. that female's cells have a single sex chromo- This is not the mourning dove, though of some while in males there is a pair. We can use similar size. No permit is required to keep it. w to represent the recessive gene for white, Strangely, few teachers have recognized its and W for the dominant allele, thus: value, though it has been used extensively in research. With its open nest, the life cycle can w w _ 0 w be followed intimately from In sire sperms dark son. early embryo, (white) w se. and the birds will thrive in a small cage for years, with a minimum of care and incon- In dam IV w venience. (dark) . eggs M4 - - dhte Three color varieties exist: blond (the most ___, p-No daughter. common), white, and dark (rare). Cole3 dis- covered that these are alternative in inheri- The dash line represents the lack of one tance and sex-linked. Perhaps the most amaz- chromosome in females. ing trick the teacher can perform is to tell the White doves once were thought to be a sex of a dove embryo two or three days old separate species, but are merely a color varietv. by its color, and prove it when the bird any pet store operators still do not know it, matures. All one must do is mate white males or try to capitalize on the myth of distinctive writh blond or dark females. When the eggs origin by calling them "Sacred White Indian are "candled" by holding them against a hole doves." The blonds generally go by the names in a cardboard before a bright light in a dark "ringneck dove," "ring dove," "Barbary dove," room, the embryo is clearly visible through "collared turtle dove," or "laughing dove." In the paper-thin shell. Embryos with black eyes French they are "tourterelle a collier," and in 18 THE AMERICAN BIOLOGY TEACHER January, 1959 A- Downloaded from http://online.ucpress.edu/abt/article-pdf/21/1/17/15565/4439058.pdf by guest on 28 September 2021 "Why is that photographer using such bad language?" The birds were posed in dim light to discourage A temporary cage made from a carton. The birds flying, with the result that they relaxed too easily. can be kept in such a cage for weeks in excellent health. For adequate exercise and for breeding a German, "die Lachtaube." Doves are generally cage about two feet in each dimension is desirable. too cheap for pet stores to get enthusiastic The feed and water cups are made from one-pint tin cans. over, but they can be procured with a little urging. and grass seeds."15Along the coast of the Red The origin of domestic doves apparently Sea they are said to be "extraordinarily plenti- goes back to Bible times, when doves were ful"; they are "found in every garden and at used as sacrifices. It is now known that the each and every watering-place . the still wvild species Streptopelia roseogrisea of N. E. hot air resounds with their monotonous took- Africa and the Red Sea region was the tookaroo, took-tookaroo. They cannot be progenitor.14 Nevertheless, there has been driven from the wells, are completely tame some confusion, started by Aldrovandi about and confiding."' Such a state of a airs suggests 1600 when he called the domestic form Turtur absence of predators such as cats. indicus. Linne changed the name to Columba In the laboratory the doves thrive on poul- risoria but still said "habitat in India." The try feed; a pound will feed a breeding pair for wild Indian species was later named Strepto- a week or more. Mash is not appreciated by pelia decaocto. Resolution of this "taxonomess" the birds however; they pre fer whole or is still not complete. Moreover, the wild species cracked grain, or pellets. Wheat and cracked of this genus can all be crossed in captivity, corn are excellent staple foods as a rule. giving more or less fertile hybrids, so that Chicken "scratch feed" is usually good. For species characters nmaybe transferred.7 21 optimum nutrition, especially when breeding, Domlestic doves have also been crossed with the birds also need a little more or better pro- mourning doves (Zenaidura macroura) but tein, such as in dried peas, and minerals. Well- the hvbrids produced were totally sterile.17 crushed shells from hard-boiled eggs furnish Crosses of female doves with male domestic the needed calcium; coarse sand dampened pigeons (Columba livia) give practically 100% with brine made from iodized table salt com- nmale hybrids, the female hybrids generally pletes the list. If the birds do not have regular failing to hatch.' The reverse cross, when suc- sunlight (not filtered by window glass) they cessful at all, gives both sexes of hybrids viable. also require a little vitamin D, which can be Onlv the male hybrids of this extreme cross given by moistening the feed occasionally with are able to breed at all, producing progeny cod-liver oil. Poultry pellets provide many of occasionally when mated with female doves. the trace requirements, but care should be These ?4-dove progeny in turn have been exercised that such feed is reasonably fresh. sterile as a rule. For tranquility, doves are best kept in pairs The habitat of the wild Streptopelia roseo- in cages of inch-mesh poultry netting. Such grisea has been described thus: "steppe land- a cage, two feet or less in each dimension, can scape with isolated groups of trees and bush be made in half an hour, at a cost of less than forest in the vicinity of milo-maize fields. The half a dollar. No lumber is required, but a diet consists almost exclusively of milo-maize large carton cut down to eight inches high, is Vol. 21, No. 1 LAUGHING DOVES IN THE LAB 19 good for the bottom. Fit the cage inside the time the parents may have a new set of eggs, carton. The wire floor of the cage should be and the presence of the youngsters becomes held up several inches above the bottom by unwelcome. The young should therefore be rods running through the carton walls. moved to their own new cage. They may be Furniture for the cage is of three sorts: stupid in learning where the feed and water (1) a perch-rod, about an inch thick; are, so that open dishes on the floor of the (2) a nest-box, such as a cigar box, con- cage for a few days are helpful. taining about half an inch of sand, Dove behavior has been of perennial interest with excelsior packed saucer-like on to many investigators,6' 22 especially in relation top; to hormone actions.2' 18 Little comment seems (3) feed and water cups. Neat cups can to have been made on one aspect however- be made from discarded tin cans (pint- panic. The gentle dove confronted with an size). With tin snips make two cuts unfamiliar object, flashing color, or strange an inch apart, down from the lip noise may suddenly explode into activity, Downloaded from http://online.ucpress.edu/abt/article-pdf/21/1/17/15565/4439058.pdf by guest on 28 September 2021 half-way. Next with pliers bend the beating against the cage sides in frantic efforts strip out and down to form a hook. to escape. The commotion is contagious if Finally bend the sharp edges of the other doves are present, and pandemonium other part of the cup inward. Such reigns briefly. Then, amazed at themselves, the cups should hang on the outside of the birds settle down to reflect, and soon tran- cage, holes for the birds to reach out quility is restored. Similarly, doves at first do being made about three inches above not like being restrained in the hand, but may floor level. Half a dozen cups per cage perch on one's palm happily without restraint. are desirable, to permit separating the There is nothing more gentle than a brood- different sorts of items, cafeteria-style. ing dove. One can take its eggs or squabs out It is possible to arrange enough cups to pro- for examination, or handle the bird without vide feed and water for a week. This solves any commotion. vacation problems to some extent. However, Often students will let a dove loose in the the exposed feed is a great attraction to mice, room and then in catching it yank out a lot of which should be kept trapped. feathers. This is no serious matter as feathers Doves are able to adapt to extremely cold regrow in a month or less, and repeated pluck- weather provided there is no wind.