Thalassemia and premarital screening: potential for implementation of a screening program among young people in Pakistan.

Pakistan has a high prevalence of ß-thalassemia (ß-thal) but lacks a screening program for its prevention. This questionnaire-based cross-sectional study was conducted in six randomly chosen non medical universities to assess the students' knowledge of ß-thal and premarital screening, and their attitude towards such a program. Comparison was made between the respondents' attitude towards premarital screening before and after providing them some information regarding the disease. Only 54.5% (207) of 380 students had heard of ß-thal, with a mean knowledge score of 13.0 ± 4.4 out of 27 questions. Most respondents were aware of the concept of premarital screening. Out of 207 students, 60.4% wanted to know if they were carriers, 69.1% wanted to know their spouse's carrier status and 59.4% wanted premarital screening to be made mandatory in Pakistan. These figures increased to 72.5, 78.3 and 67.6%, respectively after provision of written information (p values: 0.03, 0.02, and 0.01, respectively). The positive attitude towards premarital screening with low background knowledge of the disease highlights the need of a mass awareness campaign and subsequent implementation of a premarital screening program.

The evolutionary origins of ritualized acoustic signals in caterpillars.

Animal communication signals can be highly elaborate, and researchers have long sought explanations for their evolutionary origins. For example, how did signals such as the tail-fan display of a peacock, a firefly flash or a wolf howl evolve? Animal communication theory holds that many signals evolved from non-signalling behaviours through the process of ritualization. Empirical evidence for ritualization is limited, as it is necessary to examine living relatives with varying degrees of signal evolution within a phylogenetic framework. We examine the origins of vibratory territorial signals in caterpillars using comparative and molecular phylogenetic methods. We show that a highly ritualized vibratory signal--anal scraping--originated from a locomotory behaviour--walking. Furthermore, comparative behavioural analysis supports the hypothesis that ritualized vibratory signals derive from physical fighting behaviours. Thus, contestants signal their opponents to avoid the cost of fighting. Our study provides experimental evidence for the origins of a complex communication signal, through the process of ritualization.