Body temperature affects physiological processes and, consequently, has a large impact on fitness. Lizards need to thermoregulate behaviourally to maintain their body temperature within a range that maximizes performance, but there are costs associated with thermoregulation. The thermal quality of an environment is a major cost of thermoregulation because it directly affects the time and energy that must be invested by an individual to achieve and maintain an optimal body temperature for performance. According to the cost-benefit model of thermoregulation, lizards should only thermoregulate when the benefits outweigh the costs of doing so. Thus, in habitats of poor thermal quality, individuals should thermoregulate less. Using two systems, an elevational gradient and a pair of habitats that vary in the amount of solar radiation they receive, I tested the hypothesis that investment in thermoregulation by lizards is dictated by the associated costs of thermoregulating. Temperature, and thus thermal quality, decreases with elevation. I found a significant positive relationship between elevation and effectiveness of thermoregulation of Yarrow’s spiny lizards (Sceloporus jarrovii). When comparing thermoregulation of ornate tree lizards (Urosaurus ornatus) living in the thermally superior open-canopy wash habitat or the closed-canopy upland habitat, I found that habitat type was a significant predictor of accuracy of body temperature. In the poorer quality habitat, lizards had smaller deviations of body temperature from their preferred temperature range. Overall, I conclude that the thermal quality of a lizards’ environment impacts their thermoregulation in the opposite direction than predicted by the cost-benefit model of thermoregulation. This suggests that the disadvantages of thermoconformity may be greater than the costs thermoregulating as habitats become more thermally challenging.

Knowledge of the thermal ecology of a species can improve model predictions for temperature-induced population collapse, which in light of climate change is increasingly important for species with limited distributions. Here, we use a multi-faceted approach to quantify and integrate the thermal ecology, properties of the thermal habitat, and past and present distribution of the diurnal, xeric-adapted, and active-foraging Namibian lizard Pedioplanis husabensis (Sauria: Lacertidae) to model its local extinction risk under future climate change scenarios. We asked whether climatic conditions in various regions of its range are already so extreme that local extirpations of P. husabensis have already occurred, or whether this micro-endemic species is adapted to these extreme conditions and uses behavior to mitigate the environmental challenges. To address this, we collected thermoregulation and climate data at a micro-scale level and combined it with micro-and macroclimate data across the species' range to model extinction risk. We found that P. husabensis inhabits a thermally harsh environment, but also has high thermal preference. In cooler parts of its range, individuals are capable of leaving thermally favorable conditions-based on the species' thermal preference-unused during the day, probably to maintain low metabolic rates. Furthermore, during the summer, we observed that individuals regulate at body temperatures below the species' high thermal preference to avoid body temperatures approaching the critical thermal maximum. We find that populations of this species are currently persisting even at the hottest localities within the species' geographic distribution. We found no evidence of range shifts since the 1960s despite a documented increase in air temperatures. Nevertheless, P. husabensis only has a small safety margin between the upper limit of its thermal preference and the critical thermal maximum and might undergo range reductions in the near future under even the most moderate climate change scenarios.

本論文之研究目的在以成本與利益觀點，驗證產品資訊搜尋過程，消費者於對搜尋時間成本與產品資訊信心程度之主觀估計，在極大化程度對消費者產品資訊搜尋行為影響所扮演的中介變數角色，藉此瞭解產品資訊搜尋階段，極大化程度對消費者資訊搜尋行為與態度之影響機制。 極大化程度為一種個人追求最佳選擇程度之人格特質傾向。過去極大化程度在消費者行為領域之相關研究，多聚焦於探討不同極大化程度消費者之選項數量偏好、時間成本投入意願與決策後情感反應之差異，甚少有消費者資訊搜尋過程相關議題之討論。本研究認為，產品資訊搜尋實為消費者整體選擇與決策歷程最重要之階段，經常影響消費決策之最終品質，因此若要真正瞭解極大化程度對消費者選擇行為與態度差異之影響，除從極大化人格特質基本定義做為影響之解釋外，亦須藉由探討極大化程度在產品資訊搜尋過程，對消費者資訊成本與利益認知之影響中，連結出整段消費者選擇行為歷程之影響機制關係。 本論文以Ratchford (1982) 所提之「資訊搜尋之成本－利益模式 (The Cost-Benefit Model for Information Seeking)」為理論基礎，並將研究分為兩部份，研究一為探討不同極大化程度消費者在產品挑選機制與產品屬性要求標準上的差異，透過受測者對四項產品之屬性重要度評估、對特定屬性規格之期望標準，得知不同極大化程度受測者在產品屬性重視的程度、視為重要的屬性數量，以及產品屬性要求標準上之差異。研究二則採取2 (資訊延遲時間高、低)×2 (產品屬性離散程度高、低) 組間設計實驗，透過本研究設計之虛擬產品購物網站平台，讓受測者執行產品資訊搜尋任務，從中衡量受測者對產品資訊搜尋時間成本與資訊信心之主觀估計，驗證單位搜尋時間估計與單位資訊效用估計在極大化程度對受測者產品資訊搜尋數量、搜尋過程滿意度與產品知覺價值中，扮演之中介變數角色，以瞭解箇中之內在心理機制。 研究結果顯示，極大化程度與產品屬性重視程度及屬性要求標準呈現顯著正向關係，極大化受測者對產品屬性的重視程度與對產品屬性的要求標準皆較滿足化者高。足見不同極大化程度消費者對選擇之追求目標差異，會具體展現於產品遴選機制與屬性要求標準上。而經過中介變數關係檢定後也發現，極大化程度越高之受測者所估計之搜尋時間與對資訊在決策幫助上的信心越低，因而正向影響了搜尋的產品數量，搜尋時間成本與資訊效用估計亦分別成為受測者對搜尋過程滿意度以及對產品知覺價值之中介變數。 本論文之研究成果除驗證極大化選擇目標與產品遴選機制及屬性要求標準之關聯性外，亦進一步得知極大化程度影響消費者產品資訊搜尋行為與態度之內在心理機制，成功將系統性之消費者資訊搜尋經濟模式與極大化概念結合，為極大化程度研究領域帶來更深入且具理論基礎之發現。研究成果亦可作為通路或產品廠商思索產品陳列與資訊呈現方式時之參考依據，以降低顧客之主觀成本花費、提升產品資訊帶給顧客決策上的利益，提高顧客對個人整體消費過程之滿意度與所選產品之知覺價值。 / The purpose of this research is to demonstrate whether consumers’ subjective estimations of search time and product information confidence are the mediators mediating the effects of maximization tendency on consumers’ product information seeking behavior and attitude. From the perspective of information cost-benefit, the psychological mechanism will be found from this effect of personality on consumer behavior in this research. Maximization tendency was conceptualized in recent ten years to describe individual’s personality that strives for pursuing the best choice. After this concept was developed, most of the researches in this domain focused on discussing in the relationships between maximization orientation and consumers’ choice preferences such as the differences in the amount of alternatives, the aspiration to invest search time, and affective response after making decision. However seldom of them paid their attentions to the stage of product information search to probe the mechanism for the effect of maximization tendency on consumers’ searching behaviors about product information. Since the information seeking is the most important process to influence consumers’ decisions, the current study aims to explore the effects of maximization tendency on the individuals’ subjective estimations of time cost and benefit of product information. Hereby, the whole picture of the causal relationship in consumers’ information searching process would be drawn in this study. Referring to the rationales of Ratchford’s cost-benefit model, this research conducts two studies: the first part is to assess the differences in the criteria and attribute standard of consumers’ product selection with differential maximization tendencies. The second part is to conduct a 2 (the delay length of information appearance: low and high)×2 (the the dispersion of information attributes: low and high) between subject design experiments to demonstrate the mediating effect of two variables: consumers’ subjective estimation of time cost and information confidence during searching for information in the relations between maximization tendency and consumers’ information seeking behavior. The result shows the relationship between participants’ maximization orientation and their selection criteria as well as attribute demand standard exists. In general, maximizers have more complex choice criteria and higher picking standards than satisficers do when they choose the same products. The psychological mechanism is confirmed to help us understand how maximization tendency affect seeking behaviors and attitudes of product information from consumer’s product information seeking behavior and attitude. Manufacturers and store owners are suggested to apply these findings in the arrangement of alternatives and the display of product attribute information in order to reduce customers’ subjective estimation of time cost and improve their perception on information utility to, eventually, increase their satisfaction with the whole consumption experiences.

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