scispace - formally typeset
Search or ask a question
Author

Stefania Casagrande

Bio: Stefania Casagrande is an academic researcher from Max Planck Society. The author has contributed to research in topics: Kestrel & Falco tinnunculus. The author has an hindex of 19, co-authored 36 publications receiving 977 citations. Previous affiliations of Stefania Casagrande include University of Antwerp & University of Parma.

Papers
More filters
Journal ArticleDOI
TL;DR: It is suggested that intrabrood sibling competition could play a role in determining oxidative stress, and that in carnivorous birds other antioxidant molecules could be more important than carotenoids to reduce oxidative stress.
Abstract: The fitness of an organism can be affected by conditions experienced during early development. In light of the impact that oxidative stress can have on the health and ageing of a bird species, this study evaluated factors accounting for the variation in oxidative stress levels in nestlings of the Eurasian kestrel (Falco tinnunculus) by measuring the serum concentration of reactive oxygen metabolites and the serum antioxidant barrier against hypochlorite-induced oxidation. The ratio between these two variables was considered as an index of oxidative stress, with higher values meaning higher oxidative damage. Six-chick broods showed the highest level of oxidative stress, while no effect of sex was found. Age showed an inverse relationship with the oxidants and the levels of oxidative stress, with younger birds having higher levels. Hatching date, body condition, body mass and carotenoid concentration did not show any relationship with oxidants, antioxidants or degree of oxidative stress. These findings suggest that intrabrood sibling competition could play a role in determining oxidative stress, and that in carnivorous birds other antioxidant molecules could be more important than carotenoids to reduce oxidative stress.

164 citations

Book ChapterDOI
TL;DR: This chapter was originally published in the book Advances in the Study of Behavior, Volume 48, and is provided by Elsevier for the author's benefit and for the benefit of theAuthor's institution, for non-commercial research, and educational use.
Abstract: This chapter was originally published in the book Advances in the Study of Behavior, Volume 48. The copy attached is provided by Elsevier for the author's benefit and for the benefit of the author's institution, for non-commercial research, and educational use. This includes without limitation use in instruction at your institution, distribution to specific colleagues, and providing a copy to your institution's administrator.

141 citations

Journal ArticleDOI
TL;DR: In this article, the authors explore how mitochondrial aerobic metabolism influences different aspects of organismal performance, such as through changing adenosine triphosphate (ATP) and reactive oxygen species (ROS) production.
Abstract: Biologists have long appreciated the critical role that energy turnover plays in understanding variation in performance and fitness among individuals. Whole-organism metabolic studies have provided key insights into fundamental ecological and evolutionary processes. However, constraints operating at subcellular levels, such as those operating within the mitochondria, can also play important roles in optimizing metabolism over different energetic demands and time scales. Herein, we explore how mitochondrial aerobic metabolism influences different aspects of organismal performance, such as through changing adenosine triphosphate (ATP) and reactive oxygen species (ROS) production. We consider how such insights have advanced our understanding of the mechanisms underpinning key ecological and evolutionary processes, from variation in life-history traits to adaptation to changing thermal conditions, and we highlight key areas for future research.

67 citations

Journal ArticleDOI
TL;DR: The presence of differences in diet composition between neighbouring pairs and their temporal consistency suggests that the hunting skills, and in general the feeding behaviour of kestrels, is likely to represent a trait characterising a behavioural type.
Abstract: In this study, we analysed the diet of breeding kestrels (Falco tinnunculus) in a Mediterranean area with the aim to evaluate the relative importance of both hunting area and individual feeding behaviour as factors affecting prey selection Differently from the populations from middle and northern Europe which primarily feed on voles, the kestrels breeding in the Mediterranean region showed a wider diet composition As expected, hunting area features influenced the diet composition and, in general, the kestrels were feeding on what was locally more abundant However, we detected consistent differences in the diet composition between neighbouring breeding pairs which were also maintained in subsequent years Since the neighbouring birds were sharing the same hunting grounds, the differences observed were likely to reflect individual preferences or capabilities in catching some prey type regardless of their actual availability The presence of differences in diet composition between neighbouring pairs and their temporal consistency suggests that the hunting skills, and in general the feeding behaviour of kestrels, is likely to represent a trait characterising a behavioural type

61 citations

Journal ArticleDOI
TL;DR: Investigation of the yellow-orange colouration of the tarsi of the kestrel Falcotinnunculus in relation to sex, diet and to different aspects of male reproductivebehaviour suggests that in the common kestREL carotenoid based colouration is important as an indicator of male quality.
Abstract: 196.In the context of sexual selection carotenoid based signals are candidates for indicatortraits: they have to be taken up in the diet by animals, they can indicate the ability of thebearer to accumulate a limited resource, and they help in maintaining the health status.We investigated the yellow-orange colouration of the tarsi of the kestrel Falcotinnunculus in relation to sex, diet and to different aspects of male reproductivebehaviour. The colouration of the tarsi (estimated as hue) was more intense in malesthan in females. Among males, the tarsi hue was associated with the intake ofinvertebrates; this was true also if the population diet was based mainly on voles.Carotenoid based colouration was positively associated with the number of vertebratepreys delivered to the nest per time unit and with territory quality (calculated on thebasis of home-range size, habitat extension and prey availability). These results areconsistent with predictions derived from good-parent models of sexual selection,suggesting that in the common kestrel carotenoid based colouration is important as anindicator of male quality.S. Casagrande (correspondence), D. Csermely and James Tagliavini, Dipartimento diBiologia Evolutiva e Funzionale, Universita` di Parma, Parco Area delle Scienze 11/A,43100 Parma, Italy. E-mail: casagrande@biol.unipr.it. E. Pini and V. Bertacche, Istitutodi Chimica Organica ‘‘A. Marchesini’’, Facolta` di Farmacia, Universita` di Milano, ViaVenezian 21, 20133 Milano, Italy.

60 citations


Cited by
More filters
Journal Article
TL;DR: For the next few weeks the course is going to be exploring a field that’s actually older than classical population genetics, although the approach it’ll be taking to it involves the use of population genetic machinery.
Abstract: So far in this course we have dealt entirely with the evolution of characters that are controlled by simple Mendelian inheritance at a single locus. There are notes on the course website about gametic disequilibrium and how allele frequencies change at two loci simultaneously, but we didn’t discuss them. In every example we’ve considered we’ve imagined that we could understand something about evolution by examining the evolution of a single gene. That’s the domain of classical population genetics. For the next few weeks we’re going to be exploring a field that’s actually older than classical population genetics, although the approach we’ll be taking to it involves the use of population genetic machinery. If you know a little about the history of evolutionary biology, you may know that after the rediscovery of Mendel’s work in 1900 there was a heated debate between the “biometricians” (e.g., Galton and Pearson) and the “Mendelians” (e.g., de Vries, Correns, Bateson, and Morgan). Biometricians asserted that the really important variation in evolution didn’t follow Mendelian rules. Height, weight, skin color, and similar traits seemed to

9,847 citations

Journal ArticleDOI
20 Apr 1907
TL;DR: For instance, when a dog sees another dog at a distance, it is often clear that he perceives that it is a dog in the abstract; for when he gets nearer his whole manner suddenly changes, if the other dog be a friend as discussed by the authors.
Abstract: ION, GENERAL CONCEPTIONS, SELF-CONSCIOUSNESS, MENTAL INDIVIDUALITY. It would be very difficult for any one with even much more knowledge than I possess, to determine how far animals exhibit any traces of these high mental powers. This difficulty arises from the impossibility of judging what passes through the mind of an animal; and again, the fact that writers differ to a great extent in the meaning which they attribute to the above terms, causes a further difficulty. If one may judge from various articles which have been published lately, the greatest stress seems to be laid on the supposed entire absence in animals of the power of abstraction, or of forming general concepts. But when a dog sees another dog at a distance, it is often clear that he perceives that it is a dog in the abstract; for when he gets nearer his whole manner suddenly changes, if the other dog be a friend. A recent writer remarks, that in all such cases it is a pure assumption to assert that the mental act is not essentially of the same nature in the animal as in man. If either refers what he perceives with his senses to a mental concept, then so do both. (44. Mr. Hookham, in a letter to Prof. Max Muller, in the 'Birmingham News,' May, 1873.) When I say to my terrier, in an eager voice (and I have made the trial many times), "Hi, hi, where is it?" she at once takes it as a sign that something is to be hunted, and generally first looks quickly all around, and then rushes into the nearest thicket, to scent for any game, but finding nothing, she looks up into any neighbouring tree for a squirrel. Now do not these actions clearly shew that she had in her mind a general idea or concept that some animal is to be discovered and hunted? It may be freely admitted that no animal is self-conscious, if by this term it is implied, that he reflects on such points, as whence he comes or whither he will go, or what is life and death, and so forth. But how can we feel sure that an old dog with an excellent memory and some power of imagination, as shewn by his dreams, never reflects on his past pleasures or pains in the chase? And this would be a form of self-consciousness. On the other hand, as Buchner (45. 'Conferences sur la Theorie Darwinienne,' French translat. 1869, p. 132.) has remarked, how little can the hardworked wife of a degraded Australian savage, who uses very few abstract words, and cannot count above four, exert her self-consciousness, or reflect on the nature of her own existence. It is generally admitted, that the higher animals possess memory, attention, association, and even some imagination and reason. If these powers, which differ much in different animals, are capable of improvement, there seems no great improbability in more complex faculties, such as the higher forms of abstraction, and selfconsciousness, etc., having been evolved through the development and combination of the simpler ones. It has been urged against the views here maintained that it is impossible to say at what point in the ascending scale animals become capable of abstraction, etc.; but who can say at what age this occurs in our young children? We see at least that such powers

1,464 citations

Journal ArticleDOI

1,148 citations

Journal ArticleDOI
A Grant1
28 Oct 2002-Heredity
TL;DR: An excellent review of life history theory, which integrates this well with results from the empirical literature, and gives an invaluable route into the literature, with a bibliography of 1600 or so items.
Abstract: Life history biology sits on the interface between genetics and ecology, and both have made important theoretical and empirical contributions to our understanding. However, the connections between the disciplines have not always been as close as they might have been and this book takes some useful steps towards remedying this. It gives an excellent review of life history theory, and integrates this well with results from the empirical literature. After an 11-page introduction, Roff sets out ‘a framework for analysis’ in which he covers the necessary elements of quantitative and population genetics. This includes clear definitions of fitness in a range of circumstances, from density independent populations in constant environments through to the more complex situations of density and frequency dependence and environments that are spatially or temporally stochastic. Trade-offs are then examined, including a valuable analysis of potential pitfalls in studying them and ways that these can be avoided. The author then deals in turn with evolution in constant environments; stochastic environments and ‘predictable environments’. The last of these covers situations where there is environmental variation, but at least some information is available to allow individuals to make an adaptive response. The final chapter identifies 20 topics for future study. Some will find the book too dominated by theory. Others (but probably not readers of Heredity!) will find it contains too much genetics. But Roff does an excellent job of making the theory accessible, covering the essential issues and pointing to original sources for the details. Theory is related to a significant number of empirical studies, although there is room for another book reviewing the empirical literature on life histories in detail, and Roff’s book would provide a robust skeleton on which to hang this. To make my own assessment, I examined in detail Roff’s discussion of the question of fitness measures for density dependent populations in stochastic environments – an area in which I have been involved. I could not fault him – all the key references were there and the issues were made very clear without the more esoteric mathematics. I also examined some areas that I was less familiar with, and again the text was clear and easy to read. My only real criticism of the book would be that its very long chapters (more than 130 pages in one case) makes it difficult to find things. It would have been simple to address this by including the section headings on the contents pages. A minor personal quibble would be that the book usually expresses problems in terms of the intrinsic rate of increase, r, and the characteristic (Lotka) equation. A matrix formulation is often more tractable and is easier to generalise to density dependent populations and stochastic environments, so expanding on the relationship between the two would have been useful. But overall this is an excellent book. It brings together the key theory in a single place. It gives an invaluable route into the literature, with a bibliography of 1600 or so items. These features, and its identification of topics that need further study should make an important contribution to moving the field forward.

819 citations

01 Jan 1999
TL;DR: Adr1p Carbon source-responsive zinc-finger transcription factor, required for transcription of the glucose-repressed gene ADH2, of peroxisomal protein genes, and of genes required for ethanol, glycerol, and fatty acid utilization is studied.
Abstract: Adr1p Carbon source-responsive zinc-finger transcription factor, required for transcription of the glucose-repressed gene ADH2, of peroxisomal protein genes, and of genes required for ethanol, glycerol, and fatty acid utilization (Direct: ChIP-on-chip) Cat8p derepression of a variety of genes under non-fermentative growth conditions, active after diauxic shift, binds carbon source responsive elements Hap4p Subunit of the heme-activated, glucose-repressed Hap2p/3p/4p/5p CCAAT-binding complex, a transcriptional activator and global regulator of respiratory gene expression; provides the principal activation function of the complex Indirect: Microarrays-Wild type vs. TF mutant) Stp1/Stp2 Homologous transcription factors, activated by proteolytic processing in response to signals from the SPS sensor system for external amino acids; activates transcription of amino acid permease genes and may have a role in tRNA processing

489 citations