Interconnect features of W metal, recessed in an SiO2 dielectric, can be formed using a novel chemical‐mechanical polish process. Mechanical action, to continually disrupt a surface passivating film on W, and chemical action, to remove W, appear to be requirements for workability of the process. A trial process chemistry using a ferricyanide etchant is described. Removal of the W is discussed in terms of competition between an etching reaction which dissolves W and a passivation reaction to reform WO3 on the surface of the W. This novel processing technology is compared with earlier methods of fabricating metal interconnect structures.

The mating behavior of female Barbary macaques (Macaca sylvanus) has been called “promiscuous” because females mate with multiple males in rapid succession. The data presented here, based on a 9 month study of a semifree‐ranging colony, supports the idea that females do indeed mate indiscriminately and at a high rate. Five hundred six copulations were recorded for 21 females during the breeding season, and 358 of these copulations occurred when females were in extended estrous cycles. As the days that females spent in estrus increased, either because they had longer cycles or more cycles than some other females, the number of different male partners also increased. There was no association between mating behavior and either male–female friendships or male care of infants born the following birth season. Promiscuity cannot be explained by selection to confuse paternity. There is also no evidence that females exchange copulations for support or affiliation. Female Barbary macaques mate with multiple males because males are unable, or are unwilling, to stop them.

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As outlined by Darwin, sexual selection is composed of two parts, within-sex competition for mates, and mate choice. The fact that males compete for fertile females has been well established. More equivocal is the notion that females have preferences for certain males, and that those preferences have a n evolutionary effect (''female choice"). We now have a n evolutionary framework and sophisticated mathematical models to evaluate female choice. A review of the literature on primate species reveals that 20 species have exhibited some sort of preference. Females most often choose males based on familiarity, novelty, or status. But there is no evidence that selection for particular males affects conception or fitness, or male characteristics. Female sexual assertiveness is not necessarily female choice.. . . it is improbable that the unions of quadrupeds in a state of nature should be left to mere chance. It is much more probable that the females are allured or excited by particular males, who possess certain characters in a higher degree than other males: but what these characters are, we can seldom or never discover with certainty.--(=. Darwin, 1871Estrous females cannot be considered as passive resources like water and peanuts.-L. Fedigan, 1983 If it's not forced copulation, is it female choice?-D. Winkler, 1988 Nonhuman primates are studied by anthropologists to gain some understanding of the evolution of human behavior. This approach is employed because 1) humans are members of the order Primates, and thus we share a close genetic relationship with extant nonhuman primates in comparison to other mammals; 2) broad behavioral patterns have a genetic basis and they are assumed to be under similar evolutionary pressures for nonhuman and human primates; and 3) the living primates presumably reflect stages of our own primate ancestry. It follows that nonhuman primates, and their patterns of behavior, may be windows to the evolution of hominid behavior. In other words, the reproductive, ecological and social pressures that molded extant nonhuman primate behavior are probably similar, in a broad sense, to those that constrained our hominid forbears.Since W.D. Hamilton's description of kin selection in 1964, and Wilson's (1975) presentation of a sociobiological framework, anthropologists who study primates have readily applied evolutionary theory to patterns of primate behavior. Mating strategies have received a good deal of attention because they directly affect re-0 1989 Alan R. Liss. Inc.

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