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star~ve" we are particularly interested to know how specieq of animals and plants survive. An obvious and eay nnimal to investigate is the black harvester ant of the gemis Vf,rorrr~~ssor, tthose colonie~, although rare. can "till be found in the white sand desert. This specie" depends on seeds for food. yet for the last three years there has not been enough rain to bring up the annual vegetation; and thtre ha- hardly tieen a really good flowrr year for a decade. Robbery pays Our method of study is to mark a number of colonies and then follow their fate frorn month to month. And we investigate the food that the ants carry to their nests by the simple expedient of robhing the workers. It is as though a giant were to post himself outside a supermarket and, with huge tweezers. lease all persons who came out until they dropped their bundles. fn this way, without seriously upsetting the life of the colony, we are able to get a picture of the amount and kind of food that it collects every week of the year. An interesting supplementary method would be to uncover the underground granaries of non-marked colonies. But our last attempt had to stop at a depth of 12 feet. At that depth, which made further excavation impractical, we had not reached any of the main chambers, and the passageway was still spiralling down at a steep angle. We did find, however, a small store of seeds at 8 feet, and, although it is often said that ants bite off the radicles to prevent germination, these seeds sprouted when given light and moisture. One reason that the black harvester ant digs such deep nests is that its temperature tolerance is extraordinarily narrow for a desert insert. In summer, although it may be sluggishly active all night, dumping sand and refuse on the middens, it does not forage until mfliriently warmed hy the sun--around 6 a.m. Then food is hunted at top speed, for by 8 a.m. the sand is so hot that the workers have to go below, not to reappear again until the cool of evening. If a wind should arise while the ants are foragin~. all whe~l around and hurry back to the formicary. The more faniiliar one become- m ith the black har- ~wtcr ant the more '-iiipriwl ow is that GO
desert rain goes a long waj towardi ih~teiininiiig the composition of the flora that subsequently arises. And, hence. even in wet years. the annual vegetation of one year may be quite difleieiit from that of ariothei. So far, our watering experiments ]late not met the conditions required for germinaiion of the second species that is important lo the ants. for not a single comb-bur has appeared. Except for moistuie deficiency. the chief cause of mortality during the s~uiinitr V ~ Z ~aliliita, which ate verbena but not sand-mat-the lattt-r being protecicid by a milky juice that i* said to have protern-digrrtiiig powers. In October and ho;i.mljer, -wind V.J; inij destructive to seedlings because of ihc ~~~~d-Lltt~i that acompanied it. Research, such as this on the ants and tlie ~iinual vegetation of the white sand dt~siait, requires fah]? ciifi- tinuous, long-time study ol a 'ingle area. and ~ni& not seem appropiiatc fat a niohilt~ la1~oiiitoiy. But ~ t * intend that such studies are to be par1 of the plog1im in order to proxide coi~tinuity. Another idea is tlut the mobile IaLoutuq s-houlil not opeidte nnl~ tin tile hi-'nefit of Caltcrh, lidiht-i n-, would like In i-ec it uw11 ds nas the De-eit L'iLoi ituq dl Tucson, which attrarated wuik~rs from all oit'~ tliv world. \nd, tliou~li that laboratory wa? coiicviiit-(i eliiell) w ill1 pian t?. H th pl'w to gius eÃ§iua eiiruuiiigeiiieiii to the study of animals. The relation between animals and plants. a$ I-xt-inplified by haivester dills and iced?. is one 01 nidii) interlocking factors affecting survival of species. In warm, humid cliniates, a ]lev\ ilderin!.; ai i a) of orpiisms ir~ake? the regit'gdtiori and evaluation of thest> factors difficult. But in the desert, \\here the flora ami fauna are limited hj aridity. the task is le" complex. That is whj Caltecli'? nett leredrcli centei .JII wheels is de-igiitad paiticulail~ to investigdte arid region;.. The desert itself, with long periods of magnihcent weather broken by violent extremes. is an exquisite biological laboratory. There is much to be learned from it. and by studying how its plants and animals buivive the climatic extremes. -we hope to complement the woik that t.altechs Earhart I ,ciIioi atoi) ir doing with conti oiled M eathei. The mobile laboratorpnou riiufif"i il possible tor desert researchnr/i to folloz~ the rains Imiii place to place. FEBRUARY, 1957 2 3
Page 2 and 3: Frederic F. Berman, class of '46, s
Page 4 and 5: Here is an excellent opportunity fo
Page 7: a gner --SB and in Business and Eng
Page 10 and 11: ALTECH BROKE a long-'tariciir~g tra
Page 12 and 13: another modern plant Miniature Prec
Page 14 and 15: s CONTINUED learned to differentiat
Page 16 and 17: STUDENT LIFE ITTING IN THE LOFNGE i
Page 18 and 19: cool cool A glowing steel ingot and
Page 20 and 21: model so the cobalt emits the elect
Page 22 and 23: and cloudbursts of arid plares. Bec
Page 26: ALTECH QUIZ by GEORGE W. BEADLE You
Page 30 and 31: STUDENT-FACULTY CONFERENCE Small, i
Page 32 and 33: YEARS AGO.. . 11 Broadway, New York
Page 34 and 35: THE MONTH AT CALTECH Leaders of Ame
Page 37 and 38: This graph shows the relationship b
Page 39 and 40: Bill's present assignment at Wester
Page 41 and 42: FEBRUARY, 1957 tkattle, Washingran
Page 43 and 44: The development of more a& ancedy f
Page 45 and 46: Research Eng~neer Russeli Lowe rnea
Page 47 and 48: All lines drawn coincident with the
Page 49 and 50: WITH THE ELECTRONICS DIVISION OF ..
Page 51 and 52: g a snap to recor w Sensations in S
Page 53 and 54: FEBRUARY. 1957
Page 55 and 56: Can your i/~z~~gitzation identify t
Page 57: The Garrett Corporation operates un
Page 60 and 61: Changes in By-Laws THE BOARD OF DIR
Page 62 and 63: The Engineering Department at Conva
Page 64 and 65: Alumni News . . . CONTINUED Article
Page 66 and 67: New techniques.. . new equipment..
Page 68 and 69: Alumni News . . CONTINUED Not later
Page 70 and 71: I April 6 June 5 June 29 ALUMNI EVE
Page 72: GENERAL ELECTRIC OFFERS . . . The g

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