Source and nature of disturbance-chemical system in crayfish

The responses of crayfish to water from aquaria containing either undisturbed or disturbed animals were observed. The crayfish Orconectes propinquus and O. rusticus showed no response to disturbed-conspecific water. Individuals of O. virilis respond not only to disturbed crayfish but to other taxa (the leech Macrobdella decora , the darter Etheostoma exile , and rock bass Ambloplites rupestris ), but not to the painted turtle Chrsymes picta . Additional tests indicated partial responses by O. virilis to ammonium and to a chemical or chemicals released from the green gland of crayfish. Ablation experiments indicated the antennules as the site of reception of the chemicals. Additional behavioral tests indicated that detection of the disturbance chemical(s) results in the crayfish showing low-level alert for more than 15 min, once an initial priming period has passed.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44879/1/10886_2005_Article_BF01026936.pd

Market Conduct and Endogenous Lobbying: Evidence from the U.S. Mobile Telecommunications Industry

This paper empirically explores the relationship between firms' market behavior and their lobbying activities in a regulated market. In particular, we investigate whether the amount of contributions offered by cellular service providers to fund the campaigns of political parties affected market conduct in the early US mobile telecommunications industry. We structurally estimate market interactions while taking the potential endogeneity of lobbying decisions into account. Our results show that competition was more intense in those states where campaign contributions by the cellular industry have been higher. Furthermore, we reject the hypothesis that lobbying activities can be regarded as exogenous in the study of market conduct. Copyright Springer Science + Business Media, LLC 2007lobbying, campaign contributions, conjectural variations, mobile telecommunications, U.S., D72, L13, L51, L96, C31,