Browsing by Subject "ecology"

Natural scientists study a wide variety of species, but whether they have identified all studied samples correctly to species is rarely evaluated. Species misidentification in empirical research can cause significant losses of money, information, and time, and contribute to false results. Thus, I study the abundance of species misidentification and ecologists’ perceptions of such mistakes through a web survey targeting researchers from scientific institutes around the globe (including universities, research societies and museums) who completed their doctoral degree in any ecology-related field of science. I received 117 responses with either work or educational background from 30 countries. I found that species misidentification widely existed in respondents’ research: almost 70% of the respondents noticed species misidentification in their own research, while the estimated proportion of existing studies with species misidentification was 34% (95% CI: 28% - 40%). Although misidentification was mainly found during specimen collection, specimen handling and data analysis, misidentifications in reporting stages (writing, revision and after publishing) could persist until publication. Moreover, according to respondents, reviewers seldom comment about species identification methods or their accuracy, which may affect respondents’ (both leading and not leading a research team) low reporting frequency about the possibility of misidentification. Expert checking, training students, and DNA barcoding are the most prevalent approaches to ensure identification accuracy among respondents. My results imply that species misidentification might be widespread in existing ecological research. Although the problem of species misidentification is widely recognized, such an issue seldom be appropriately handled by respondents. To increase the accuracy of species identification and maintain academic integrity, I suggest that researchers need to focus more on the study species (e.g., sampling process, identification method, and accuracy) when writing and reviewing papers. Furthermore, I appeal for guidelines about reporting species identification methods and their accuracy in papers, as well as research on education about identification skills in universities, as these two topics may constrain the precision of species identification.

The general structure of the vertebrate brain is highly conserved. However, a large amount of variation exists in brain size and shape, both regarding the whole brain and its subdivisions. This variation is caused by selection acting on species’ behavioural traits and shaping the evolution of the brain in the same process. It is known that one of the factors affecting vertebrate brain morphology is ecology, including habitat complexity, activity patterns and diet. The effects of diet on brain size have been studied in primates, bats and small mammals, where frugivory in primates and bats and insectivory in small mammals, are linked to larger brains. The effect of diet on brain morphology has not been studied in squamate reptiles (lizards and snakes) and the ecological factors behind size and shape variation are largely unknown in squamates compared to other vertebrates. Squamates show large diversity in diet preference as well as feeding behaviour in general, which makes them a suitable model organism to study brain evolution. Further, squamates have highly developed nasal chemical senses that are important for feeding behaviour. These factors in mind, it would be expected that diet has an effect on squamate brain morphology, and especially the brain regions important for feeding behaviour, such as the olfactory bulbs in the forebrain. To study the effects of diet on squamate brain size and shape, the brains of 51 squamate species were micro-CT scanned and 3D-brain surfaces were generated for each species. The species were categorized into four diet groups: carnivorous, herbivorous, omnivorous and insectivorous. To analyse shape and size change across species and diet groups, 73 landmarks were placed on each 3D-brain surface, covering all brain regions: olfactory bulbs, cerebral hemispheres, telencephalon, diencephalon, midbrain, cerebellum and hindbrain. The results from this study show that diet affects significantly the shape of the whole squamate brain, as well as the size of the telencephalon. Telencephalon size differed significantly between the herbivorous and carnivorous groups. Diet had no significant effect on the other brain subdivisions studied here, including the olfactory bulbs. Diet is a large part of a species’ ecology and it is very complex behaviour involving several senses and brain regions, which could explain the results obtained from this study. The results from this study are preliminary, but they indicate that diet could be one of the factors affecting brain morphology in squamates. In the future, including other factors of feeding behaviour than food choice and analysing the effects of diet on a deeper level, such as including brain regions within the brain and analysing cellular organization, could shed some new light on how diet affects squamate brain morphology.

As biodiversity loss is identified to be one of the pressing environmental challenges today, Finnish cities have begun to follow in the footsteps of many European cities by creating urban greening plans in the form of increasing meadow habitats. The ecological and economic benefits of urban meadows are well understood, but when meadow habitats are brought into people’s everyday environments, it is important to consider how it affects people’s environmental aesthetic experiences. ‘Aesthetics’ is often understood solely as individual preferences, but the aim of this thesis was to address the aesthetic appreciation of meadows through the field of environmental aesthetics. Combining the fields of environmental aesthetics and ecology, this study provides a fresh perspective to the value debate over urban meadows. The analysis of the work approached the topic from the perspective of Finnish cities. After compiling the operational programs that solely consider urban meadows, qualitative content analysis was used to analyze what ecological and aesthetic aspects are brought up in the documents and how they are valuated. To emphasize the aesthetic perspective, it was further investigated through discourse analysis whether there are consistent ways in which cities construct an image of the aesthetic values of urban meadows. The content analysis showed that the documents have both ecological and aesthetic viewpoints. The ecological content emphasized that meadows are important tool in increasing biodiversity and also provide recreational possibilities for people. The aesthetic content focused on the cultural-historical role of the meadows as well as the experiences provided by the meadows. Based on the content analysis, three uniform discourses were identified throughout the documents. The first relates to meadows which are the remains of cities’ agricultural history, and their cultural and ecological values are easily recognizable. The second refers to meadows that are currently emerging from other green types such as lawns and grasslands reverting to woodland. They are seen as having ecological and recreational value, but as they are unlikely to meet the expectations for flowering meadows, city officials want to inform citizens about the ecological qualities of these meadows to avoid negative feedback. The last discourse focuses on the experiential side of meadows, but instead of talking about the environmental aesthetic experience as understood in theoretical research, the argumentation is restricted to visual and recreational experiences. The way in which the aesthetic qualities, values and experiences of urban meadows are understood in a professional context reflects the way in which they are presented to the users of green areas. This thesis has revealed that the terminology used in the documents referring to environmental aesthetics is insufficient and does not correspond to the concepts presented in the theory of the work. Expanding the debate on environmental aesthetics would turn the goal of ‘people tolerating unordered ecosystems’ to ‘how can unordered ecosystems be aesthetically appreciated’. While informing citizens about the ecological benefits of urban meadows, they should also be informed about the potential aesthetic values of urban meadows, such as wildness, aesthetic diversity, and how the ordinary environment becomes extraordinary.