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As evolutionary biologists have always been concerned with the genetic basis for the emergence of complex phenotypes, advances in genomics and systems biology are facilitating a paradigm shift of molecular evolutionary biology toward a better understanding of the relationship of genotypes and phenotypes. From an evolutionary perspective, the central question is whether natural selection is a necessary and/or sufficient force to explain the emergence of genomic and cellular features that underlie the building of complex organisms. Lynch has criticized the adaptive hypothesis for the origins of organismal complexity, claiming that nothing in evolution makes sense in light of population genetics that takes the effects of mutation, genetic drift, and natural selection into account. The importance of mutation types and genetic drifts on the phenotype evolution has also been emphasized by Nei and his associates. One plausible approach to resolving these fundamental issues is to model the features of biological complexity as parameters instead of emerged properties, under the principle of population genetics and molecular evolution. This chapter discusses some recent results in this trend.

This chapter examines host-fruit-odor discrimination in the apple maggot fly, Rhagoletis pomonella, and its role in sympatric speciation via host-plant shifting. It shows that R. pomonella flies both positively orient to the odor of their respective natal host fruits and avoid non-natal odor. F₁ hybrids between apple- and hawthorn-infesting host races of R. pomonella generally fail to orient to the fruit odor of either apples or hawthorns, suggesting that the evolution of new host-discrimination behaviors can generate significant postzygotic as well as premating reproductive isolation when insects must find appropriate host plants in a timely manner to mate and oviposit. The chapter discusses the adaptive zone hypothesis, ecological adaptation, host-specific mating, reproductive isolation, the pioneering work of Tom Wood and Ron Prokopy in the study of insect behavior and diversity, the natural and life history of R. pomonella, behavioral testing using synthetic fruit volatile blends, genetic analysis of fruit-odor discrimination, the physiological basis for fruit-odor discrimination, and the theoretical significance of fruit-odor discrimination studies. It concludes by discussing the generality of the Rhagoletis findings to other phytophagous insects.

Although the efficient market hypothesis (EMH) is the leading theory describing the behavior of financial markets, researchers have increasingly questioned its efficacy since the 1980s because of its inconsistencies with empirical evidence. This challenge to EMH has resulted in the development of new concepts and theories. These new concepts reject the assumption of investor rationality. The most promising and convincing among these are the adaptive markets hypothesis, overreaction hypothesis, underreaction hypothesis, noisy market hypothesis, functional fixation hypothesis, and fractal market hypothesis. The chapter provides a brief description of these theories and proposes using a behavioral perspective to analyze financial markets.

Colonization and dispersal has four parts: (1) causes of colonization; (2) success of colonizations; (3) the role of extinction of surface populations in speciation; and (4) the extent of subsurface dispersal. Discussion of these questions and processes in shallow subterranean habitats (SSHs) is modified compared to deeper subterranean habitats because barriers to colonization are less and because SSHs often have a different spatial distribution relative to caves. Animals may enter SSHs because of deteriorating surface conditions or favourable subterranean conditions. Species exapted to environments with some similarities to SSHs (e.g. leaf litter) are more likely to succeed, but prediction of which groups will be successful in SSHs is only partially possible. According to the Climate Relict Hypothesis, speciation should be allopatric as a result of the extinction of surface populations, and according to the Adaptive Shift Hypothesis, speciation should be parapatric with a strong selection gradient. Among lava tube faunas in the tropics, there are good examples of both allopatric and parapatric speciation. Two datasets, one on epikarst copepods from Slovenia and one on hypotelminorheic amphipods from the eastern USA, were extensive enough to examine the likely extent of subsurface dispersal among SSHs. In the case of copepods, species in larger numbers of drips were also in a larger number of caves, indicating the distribution was the result of subsurface dispersal. Body size in Stygobromus amphipods in seepage springs was a good predictor of both occupancy and range, with larger species having larger ranges and occupying more seepage springs.

Lava tubes are concentrated at plate boundaries of the Earth’s crust, and formed by surface cooling of lava or by sequential lava flows. Even though they are very close to the surface, environmental fluctuations, especially temperature, are often very small. Organic carbon is brought into the cave by percolating water (where it exists), organic matter entering through cracks, and tree roots (especially Metrosideros polymorpha in Hawaii). Species may colonize lava tubes either as the result of some climate change causing extinction of the surface populations (Climate Relict Hypothesis) or by active invasion and parametric speciation (Adaptive Shift Hypothesis). In addition to loss of eyes and pigment, Oliarus planthoppers show convergent morphological changes in the tibia and tarsus associated with the ability to move on wet surfaces. Adaptation can be quite rapid, taking perhaps 10,000 years, and may be examples of the most rapid speciation reported for any animal group. The two most well studied and biologically diverse lava tube regions are the Hawaiian Islands and the Canary Islands. Both have groups not commonly found elsewhere, especially earwigs, sandhoppers, and thread-legged bugs.

Colonization and speciation in subterranean environments can be conveniently divided into four stages. The first step is colonization of subsurface environments. There is a constant flux of colonists into most subterranean habitats. The second step is the success (or failure) of these colonizations. The third step is speciation. Under the Climate Relict Hypothesis (CRH) surface populations go extinct but under the Adaptive Shift Hypothesis (ASH) they do not necessarily do so, and speciation can be parapatric. There is strong evidence for the CRH among temperate zone fauna, and growing evidence for the ASH in tropical caves, especially lava tubes. The final step is possible further speciation as a result of subsurface dispersal. Detailed analysis of the evolutionary history of the isopod A. aquaticus in the Dinaric karst, diving beetles Paroster in a calcrete aquifer in Western Australia, and trogloxenic Leopoldamys neilli in Thailand reveal some of the complexities of species’ phylogeography.

For anyone interested in investments, fascination with hedge funds is almost inevitable. This enthusiasm occurs because amid the ocean of dismal performances in the asset management industry, top-performing hedge funds still manage to garner unbelievable returns even during economic downturns. This chapter explores the economics behind these supersecretive alternative investment vehicles and finds that their functioning can be broadly explained through four different economic paradigms: (1) the principal-agent framework, (2) the adaptive market hypothesis, (3) the governance framework, and (4) the factor theory framework. The chapter indicates why hedge funds are so important to society in general and financial markets in particular despite the fact that only qualified investors can invest in them.

Private equity (PE) does not fit easily into the standard risk-return Markowitz portfolio optimization framework used in the investment portfolios of institutional and other investors. The concepts of return, risk, and correlation in modern portfolio theory cannot be properly defined because no liquid market with daily observable prices exists. Therefore, good portfolio management requires a deep understanding of all the idiosyncrasies of PE investments and how they interfere with standard portfolio management. Alternative frameworks such as behavioral finance and adaptive market hypothesis are discussed. While integrating PE into a wider portfolio is problematic, designing a portfolio on its own is more straightforward. Different approaches are discussed especially on how diversification through various dimensions can be attained.