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

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"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. Rapid ing may even be of interest for study. chilling may howvever be dangerous to health. Surplus young should be given to students Doves are susceptible to about the same range or disposed of to pet shops. Some pet shops of diseases and parasites as are pigeons,10 but will board the birds over summer. In any case, are less robust. Ordinarily if doves act healthy don't just turn the birds loose out of doors. they are free of trouble, and will live and Freedom for laughing doves is no laughing breed for a number of years. In case of illness, matter, as they are easy prey for cats. Much hodge-podge medication is not recommended. better to pickle them for a lesson in anatomy. If the bird does not recover in a couple of Source References weeks with isolation, rest and good food, it is 1. Archer, G. F., and E. M. Godman, "Birds of best killed. An exception is infection of the British Somaliland and the Gulf of Aden." Lon- eye, which can become chronic. Rubbing with don: Gurney and Jackson. 1937. carbolated Vaseline or aureomnycin has been 2. Bennett, M. A., "The social hierarchy in ring found curative. doves. II. The effect of treatment with testos- terone proprionate." Ecology 21:148-165. 1940. The phenomenal growth of baby doves is 3. Cole, L. J., "A triple allelomorph in doves and always fascinating. Two eggs are laid, about its interspecific transfer." Anatomical Record 40 hours apart, and then incubation begins. 47:389. 1930. Hatching occurs in two weeks, and the young, 4. Cole, L. J., "A study of hybrid doves." Avi- culture (series 2) 2:27-30. 1930. helpless fuzzy babies, are fed "pigeon milk" by 5. Cole, L. J., and W. F. Hollander, "Hybrids of both parents. This is a curdy secretion from pigeon by ring dove." American Naturalist the walls of the crop, induced by the pituitary 84:275-308. 1950. hormone prolactin, which was first discovered 6. Goodwin, D., "Observations on the voice and in experiments with doves and pigeons.16 The some displays of certain pigeons." Avicultural Mag. 62:17-70. 1956. baby squabs rapidly grow feathers and when 7. Irwin, M. R., "Evolutionary patterns of antigenic a month old are as big as their parents. By this substances of the blood corpuscles in Colum- 20 THE AMERICAN BIOLOGY TEACHER January, 1959

bidae." Evolution 7:31-50. 1953. harmony in definition. The author portrays the 8. Lahr, E. L., and 0. Riddle, "The action of creation of life as the verification of freedom steroid hormones on the mature dove testis." itself, dignifying man as a self-reliant creature Endocrinology 35:261-266.1944. whose only restraints are the basic ethics of the 9. Lehrman, D. S., and P. Brody, "Oviduct response will to live. to estrogen and progesterone in the ring dove (Streptopelia risoria)." Proceedings, Society for Exper. Biol. and Medicine 95:373-375. 1957. 10. Levi, W. M., "The Pigeon." Second ed., 667 pp., Fishing -for Nematodes illus. Levi Publ. Co., Sumter, S. C. 1957. MARYEILEEN COSTA 11. Makino, S., T. Udagawa, and Y. Yamashina, New York "Karyotype studies in birds. II. A comparative Ithaca, study of chromosomes in the Columbidae." "This is like fishing for trout with an an- Caryologia 8:275-293. 1956. chor," exclaimed a new, assistant in Cornell 12. Miller, W. J., "Silky plumage in the ring neck dove." Jour. of Heredity 47:37-40. 1956. University's nematode research laboratory. Downloaded from http://online.ucpress.edu/abt/article-pdf/21/1/17/15565/4439058.pdf by guest on 28 September 2021 13. Miller, W. J., "The hybrid substance of the The assistant was actually "fishing," but her erythrocytes of the hybrids between Coluniba "fish" were smaller than most-in fact, they livia and Streptopelia risoria."Genetics 41:700-714. were microscopic. It involved removing in- 1956. 14. Newman, T. H., "The rosy grey turtle dove and dividual nematodes from the liquid medium, others." Avicultural Mag. (series 3) 12:100-104. using a bamboo splinter. 1921. Nematodes are round worms, but set off 15. Reichenow, A., "Die Vogel Afrikas." vol. 1, in a class all bv thenmselves.They are closely p. 413. Neudamm: J. Neumann. 1900. 16. Riddle, O., "Endocrines and constitution in doves related to a number of the invertebrate ani- and pigeons." Carnegie Inst. of Wash., publ. 572. mals, an example being the rotifers. The par- 1947. asitic nematodes are often called eelworms be- 17. Riddle, O., and M. W. Johnson, "An unde- cause they resemble in general form and shape in dove scribed type of partial sex-reversal an eel, and thev have undulating movements hybrids from a sub-family cross." Anatomical Record 75:509-527. 1939. in the water. How many different kinds of 18. Riddle, O., and E. L. Lahr, "On broodiness of nemas are there? AMany!Besides the free-liv- ring doves following implants of certain steroid ing or saprophvtic nemas, there are nemas hormones." Endocrinology 35:255-260. 1944. parasitic to plants, animals and insects. In 19. Staples-Browne, R., "On the crossing of some species of Columbidae and the inheritance of other words, nematodes exsist in or on almost certain characters in their hybrid offspring." everv form of life and in almost every place. Journal of Genetics 13:153-166.1923. The nematodes varv in size from one-sixty- 20. Taibel, A., "Ibridi artificiali interspecifici nel fourth of an inch in length to some which genere Streptopelia Bp." Atti, Societa Italiana di Scienze Naturali 88:171-190. 1949. are over a yard long. 21. Tange, M., "Further data on the crossing of Elephantiasis, a disease of humans, is caused albino ring doves with white ones." Jour. Faculty by a nematode which is not common in this of Agric., Kyushu University (Japan) 9:127-142. part of the wvorld. Even though free-living 1949. are as to ones should 22. Whitman, C. O., Posthumous works. nemas easv find, parasitic vol. 1. "Orthogenetic evolution in pigeons," be used to demonstrate in the classroom be- edited by 0. Riddle. cause of their economic importance. One of vol. 2. "Inheritance,fertility and the dominance the better known plant parasites is the Golden of sex and color in hybrids of wild species Nematode. So named because of the coloi of pigeons," edited by 0. Riddle. vol. 3. "The behavior of pigeons," edited by of the swvollen female, it is a major potential H. A. Carr. Carnegie Inst. of Wash. threat to the potato industrv of the United publ. 257. 1919. States. To date this nenmatode has been con- fined to Long Island because of rigid quar- BOOKSFOR BIOLOGISTS antine laws, which even prohibit the shipment THRESHOLDSOF EXISTENCE,Upton C. Ewing, 286 of live specimens for research purposes. Only pp, $3.75, Philosophical Library, New York, people living on Long, Island would be likelv New York, 1956. to find the Golden Nemnatode in their soil. Evolution is here set forth as manifesting in the repetition of criteria a principle through Fortunately for the biologv teacher, one of which creation is realized: a principle which ap- the most common genera, Pratylenchus, is proaches the long sought after postulate through also one of the easiest to find and identify. A which both science and religion may find a good place to find Pratylenchus is in the