Effects of selective episodes in the field on life history traits in the bumblebee Bombus terrestris

Natural selection has different fitness consequences when it acts during different life cycle stages of an organism. In social insects, for example, the colony foundation and early colony growth is a critical time period with high probability of failure. Here we used colonies of the bumblebee Bombus terrestris L. to test whether selective episodes at different life cycle stages result in differences in colony performance and fitness. The timing of a selective episode was varied by field exposure of colonies, either permanently or during a short period at three different colony life cycle stages – early, middle, or late in the cycle. We found that selective episodes at different life cycle stages did not affect maximal size, fitness or survival of colonies, or the time span between colony foundation and reproduction. Instead, the colonies were able to compensate for costs encountered by delaying reproduction. This might have important fitness consequences, since later emerging sexuals might be faced with harsher environmental conditions and increased costs of finding a mate. In addition, an important component of selection might be parasitism and the resulting resource allocation to the immune system. We here measured the generalized immune response (i.e. encapsulation response) of early produced workers as an indicator of a colony's capacity to defend against parasitism. Encapsulation response correlated positively with eventual colony size and fitness, indicating that this measure of "immunocompetence" correlates with important life history traits.     

Inflammation,Aging, and Cancer: Tumoricidal Versus Tumorigenesis of Immunity

Acute inflammation is a highly regulated defense mechanism of immune system possessing two well-balanced and biologically opposing arms termed apoptosis (‘Yin’) and wound healing (‘Yang’) processes. Unresolved or chronic inflammation (oxidative stress) is perhaps the loss of balance between ‘Yin’ and ‘Yang’ that would induce co-expression of exaggerated or ‘mismatched’ apoptotic and wound healing factors in the microenvironment of tissues (‘immune meltdown’). Unresolved inflammation could initiate the genesis of many age-associated chronic illnesses such as autoimmune and neurodegenerative diseases or tumors/cancers. In this perspective ‘birds’ eye’ view of major interrelated co-morbidity risk factors that participate in biological shifts of growth-arresting (‘tumoricidal’) or growth-promoting (‘tumorigenic’) properties of immune cells and the genesis of chronic inflammatory diseases and cancer will be discussed. Persistent inflammation is perhaps a common denominator in the genesis of nearly all age-associated health problems or cancer. Future challenging opportunities for diagnosis, prevention, and/or therapy of chronic illnesses will require an integrated understanding and identification of developmental phases of inflammation-induced immune dysfunction and age-associated hormonal and physiological readjustments of organ systems. Designing suitable cohort studies to establish the oxido-redox status of adults may prove to be an effective strategy in assessing individual’s health toward developing personal medicine for healthy aging.     

Comparing demographic parameters for philopatric and immigrant individuals in a long-lived bird adapted to unstable habitats

Theoretical models about the benefits of philopatry predict that immigrant fitness can be higher, lower or similar to that of philopatrics depending on habitat heterogeneity, dispersal costs, distance between patches or population densities. In this study, we compared transience rates, local survival and recruitment among philopatric and immigrant individuals of Audouin’s gull Larus audouinii, a long-lived bird with high dispersal capacities. Several previous studies have shown that these capacities were probably the result of adaptation to unstable and highly discrete habitats; hence, we tested the hypothesis that fitness components for philopatrics and immigrants were similar. During 1988–2006, ca. 27,800 chicks were marked in 31 colonies in the western Mediterranean metapopulation, and more than 52,000 resightings were made in a single, high-quality colony, to estimate local demographic parameters by capture–recapture analyses. Results suggest that, even though parameters related to site-tenacity (e.g. recapture rates) were higher for philopatrics than for immigrants, survival and recruitment were fundamentally similar. Small differences between philopatrics and immigrants were probably influenced by a highly suitable habitat at the study site, which reduced dispersal costs for immigrants; furthermore, the similarities in most fitness components were also probably the result of a life-history strategy of a species living in unpredictable, unstable habitats with high emigration rates among local populations, and with a relatively low cost of dispersal.     

Aggressive and Docile Colony Defence Patterns in Apis mellifera. A Retreater–Releaser Concept

Colony defence in Apis mellifera involves a variety of traits ranging from ‘aggressive’ (e.g. entrance guarding, recruitment of flying guards) to ‘docile’ (e.g. retreating into the nest) expression. We tested 11 colonies of three subspecies (capensis, scutellata, carnica) regarding their defensiveness. Each colony was selected as reportedly ‘aggressive’, ‘intermediate’ or ‘docile’ and consisted of about 10,000 bees. We applied three stimulation regimes (mechanical disturbance, exposure to alarm pheromones, and the combination of both) and measured their behaviours by tracking the rates of outflying bees at the entrance sites of the test hives. We provided evidence that for mechanical disturbances the test colonies resolved into two response types, if the ‘immediate’ defence response, assessed in the first minute of stimulation, was taken as a function of foraging: ‘releaser’ colonies allocated flying guards, ‘retreater’ colonies reduced the outside-hive activities. This division was observed irrespective of the subspecies membership and maintained in even roughly changing environmental conditions. However, if pheromone and mechanical stimulation were combined, the variety of colony defensiveness restricted to two further types irrespective of the subspecies membership: six of nine colonies degraded their rate of flying defenders with increasing foraging level, three of the colonies extended their ‘aggressiveness’ by increasing the defender rate with the foraging level. Such ‘super-aggressive’ colonies obviously are able to allocate two separate recruitment pools for foragers and flying defenders.     

Effects of NaCl stress on proline and cation accumulation in salt sensitive and tolerant turfgrasses

Summary Concentrations of proline, sodium and potassium in shoot tissues of five turfgrass species were measured following exposure to 170 mM NaCl salinity stress. Salt tolerant ‘Fults’ alkaligrass and ‘Dawson’ red fescue restricted the accumulation of Na-ions to significatnly low levels compared to the salt sensitive Kentucky bluegrasses (‘Adelphi’ and ‘Ram I’) and ‘Jamestown’ red fescue. Accumulation of proline began in all species within 24 h of initiation of salt stress but at a more rapid rate and higher overall concentration for ‘Fults’ alkaligrass. Proline levels were variable and too low in relation to sodium accumulations to have any significant osmoregulatory role in salt tolerance among all cultivars tested with the possible exception of alkaligrass.     

Characterised and Projected Costs of Nonindigenous Species in Canada

Biological invasions by nonindigenous species (NIS) can have adverse effects on economically important goods and services, and sometimes result in an ‘invisible tax’ on natural resources (e.g. reduced yield). The combined economic costs of NIS may be significant, with implications for environmental policy and resource management; yet economic impact assessments are rare at a national scale. Impacts of nuisance NIS may be direct (e.g. loss of hardwood trees) or indirect (e.g. alteration of ecosystem services provided by growing hardwoods). Moreover, costs associated with these effects may be accrued to resources and services with clear ‘market’ values (e.g. crop production) and to those with more ambiguous, ‘non-market’ values (e.g. aesthetic value of intact forest). We characterised and projected economic costs associated with nuisance NIS in Canada, through a combination of case-studies and an empirical model derived from 21 identified effects of 16 NIS. Despite a severe dearth of available data, characterised costs associated with ten NIS in Canadian fisheries, agriculture and forestry totalled $187 million Canadian (CDN) per year. These costs were dwarfed by the ‘invisible tax’ projected for sixteen nuisance NIS found in Canada, which was estimated at between $13.3 and $34.5 billion CDN per year. Canada remains highly vulnerable to new nuisance NIS, but available manpower and financial resources appear insufficient to deal with this problem. An erratum to this article is available at .     

The influence of hybridization on colony structure in the ant species Temnothorax nylanderi and T. crassispinus

The parapatric sibling ant species Temnothorax nylanderi and T. crassispinus hybridize in the contact zone in the Franconian Jura, Southern Germany. Aim of our study was to investigate the impact of hybridization on colony composition and fitness. We classified colonies as either ‘pure’ or containing hybrids by determining their allozyme pattern at GPI, an enzyme that is fixed for different alleles in the two parental species, and quantified their reproductive output. Most colonies with hybrid workers had a T. crassispinus queen. Colonies with heterozygous, hybrid workers produced more young workers than colonies of the parental species but similar numbers of male and female sexuals. Female sexuals from colonies with heterozygous workers had a significantly lower weight than female sexuals from pure colonies. Only a single reproductive queen was found to be heterozygous, suggesting reduced fitness of hybrid queens. As in the parental species, hybrid colonies appear to be frequently taken over by alien queens, which obscures the genetic colony structure. Received 6 April 2006; revised 10 June 2006; accepted 15 June 2006.     

Effect of low doses of gamma irradiation on in vitro growth of grapevine

Shoot tips and single node explants of two rootstocks (R.99 and 3309) and two varieties (‘Helwani’ and ‘Cabernet Franc’) of grapevine cultured on DSD1 media for a period of 60 days, were irradiated with 0, 2, 5 and 7 Gy doses of gamma irradiation. Shoot length of ‘Helwani’ and ‘Cabernet Franc’ was increased by 7 Gy irradiation. The 5 Gy dose increased the number of roots in plants of the two rootstocks and ‘Helwani’. Root length of ‘Helwani’ and ‘Cabernet Franc’ at the 2 and 7 Gy doses were significantly higher than those of the non-irradiated control. A similar effect was noticed on R.99 rootstock subjected to 5 Gy. Five Gy also increased the dry weight of the R.99 rootstock, whereas 2 and 7 Gy had a similar effect on ‘Helwani’ and ‘Cabernet Franc’. Number of leaves of plants exposed to 5 and 7 Gy was increased when compared with the non-irradiated control. This revised version was published online in June 2006 with corrections to the Cover Date.     

Slow-growth storage of single node shoots of apple genotypes

A landrace (‘Moscatella’) and a commercial cultivar (‘Starkspur Red’) of Malus pumila Mill. were maintained and proliferated in vitro for ≥ four years. A factorial experiment, planned to evaluate the response of the two cultivars in conservation in determined slow growth conditions, was carried out for eighteen months. Single node cuttings were stored in 4 different media, at 4 °C, in dark conditions, in microvessels to assess the feasibility of reducing space in in vitro gemplasm banks. Culture viability after storage was evaluated after 6, 8,12 and 18 months of storage. Both varieties showed high survival percentages for up to a year of conservation, but the landrace's capability to resume growth dropped dramatically afterwards. On the contrary, ‘Starkspur Red’ maintained substantially unchanged capacity of resuming vigorous growth after 18 months of conservation. Overall, microvessels appeared to be suitable for storing single node cuttings under slow growth conditions up to a year at least. The described techniques could be useful for in vitro germplasm collections where frequent subculturing enhances the risk of genetic changes and personnel, energy and materials costs limit the amount of genotypes that can be managed. This revised version was published online in June 2006 with corrections to the Cover Date.     

Immunomodulation Therapy for Invasive Aspergillosis: Discussion on Myeloid Growth Factors,Recombinant Cytokines,and Antifungal Drug Immune Modulation

Understanding fungal pathogenesis and host-pathogen immune interaction at various stages of infection is critical to examine strategies for bolstering antifungal immune defenses. Recombinant myeloid growth factors, especially granulocyte-macrophage colony-stimulating factor and the protagonist T helper (Th) 1 cytokine, interferon-γ, are most frequently used in patients with refractory invasive aspergillosis. These cytokines are given alone or in combination and have also been used together in neutropenic patients receiving donor granulocyte transfusions. Recently, a number of investigators have presented provoking data regarding auxiliary effect of conventional antifungal drugs on hosts’ immune response and pathogen’s susceptibility for antifungal immune defenses. Antifungal immunotherapy and its ameliorative role in treatment for Aspergillus disease will need clinical trials that 1) consider well-characterized fungal disease; 2) illustrate underlying immune defect(s) (such as Th1 vs Th2, vs Th17 and functional status of natural killer and effector scavenger cells); 3) include a more specific patient population; 4) include standardized antifungal drug therapy; and importantly 5) consider its impact on hosts’ immune response and changes in pathogen’s susceptibility and virulence. At present, immunotherapy is reserved for patients with life-threatening invasive fungal disease in whom conventional antifungal drug therapy has failed, or for patients with advanced fungal disease and with factors associated with high probability of failure of conventional therapy alone.     

Leaf pubescence mediates the abundance of non-prey food and the density of the predatory mite Typhlodromus pyri

Plants with leaves having numerous trichomes or domatia frequently harbor greater numbers of phytoseiid mites than do plant with leaves that lack these structures. We tested the hypothesis that this pattern occurs, in part, with Typhlodromus pyri because trichomes increase the capture of pollen or fungal spores that serve as alternative food. Using a common garden orchard, we found that apple varieties with trichome-rich leaves had 2–3 times more pollen and fungal spores compared to varieties with trichome-sparse leaves. We also studied the effects of leaf trichome density and pollen augmentation on T. pyri abundance to test the hypothesis that leaf trichomes mediate pollen and fungal spore capture and retention and thereby influence phytoseiid numbers. Cattail pollen (Typha sp.) was applied weekly to mature ‘McIntosh’ and ‘Red Delicious’ trees grown in an orchard and, in a separate experiment, to potted trees of the same varieties. ‘McIntosh’ trees have leaves with many trichomes whereas leaves on the ‘Red Delicious’ trees have roughly half as many trichomes. With both field-grown and potted trees, adding cattail pollen to ‘Red Delicious’ trees increased T. pyri numbers compared to ‘Red Delicious’ trees without pollen augmentation. In contrast, cattail pollen augmentation had no effect on T. pyri populations on ‘McIntosh’ trees. Augmentation with cattail pollen most likely supplemented a lower supply of naturally available alternative food on ‘Red Delicous’ leaves and thereby enhanced predator abundance. These studies indicate that larger populations of T. pyri on pubescent plants are due, in part, to the increased capture and retention of pollen and fungal spores that serve as alternative foods. This revised version was published online in July 2006 with corrections to the Cover Date.     

Ochratoxin A Analysen im Blut von Arbeitnehmern in der Abfallwirtschaft

Tasks such as manual sorting of domestic wastes for recyclable goods and the deposition of various materials may result in inhalation of mycotoxin-containing aerosols. Ochratoxin A (OTA) was analyzed in blood samples from workers employed at waste handling facilities in Southern Germany to assess the potential impact of this mycotoxin, and explore its use as a biomarker of exposure to bioaerosols. Results from this analysis are reported: OTA serum levels (median values) in subgroups of workers involved in waste deposition (n=76 ‘Deponierer’) or in waste sorting (n=60 ‘Wertstoffsortierer’) were 0.36 and 0.53 ng/ml, respectively. Both groups are natives of countries within the European Community (EU). In waste sorters who were born in other European (non-EU) countries (n=72) or elsewhere (n=12 from Asia, Africa), the OTA serum levels were 0.50 and 0.37 ng/ml, respectively. In controls (n=84 office clerks at the facilities; EU citizens) the median OTA value was 0.39 ng/ml. Comparing the different groups, and previously published data on median OTA levels in the general population (0.21 ng/ml) which result from dietary (background) exposure to OTA in Germany, our data point to an additional uptake of this mycotoxin by inhalation in workers with exposure to bioaerosols. The results support the view that apart from the pathogenic and allergological relevance of microbial emissions from garbage, secondary fungal metabolites, and thus toxicological aspects, deserve further attention.

Presented at the 25^th Mykotoxin Workshop in Giessen, Germany, May 19–21, 2003     

Intradiurnal periodicity of fungal spore concentrations (Alternaria, Botrytis, Cladosporium, Didymella, Ganoderma) in Cracow, Poland

Aerobiological monitoring enables the definition of seasonal fungal spore concentrations and also intradiurnal time when the highest concentrations of spores could cause or increase allergy symptoms. These data are useful to estimate symptoms of disease, duration of infection and how advanced the illness is in people suffering from fungal allergens. The aim of the study was to compare the concentrations of fungal spores (Alternaria, Botrytis, Cladosporium, Didymella, Ganoderma) during dry and rainy periods and to analyse their intradiurnal changes. Average daily spore concentrations in dry and rainy periods were compared, using z test, separately for each taxon, season and for a combined 3-year period. Intradiurnal periodicity of fungal spore concentrations was analysed on the basis of three complementary diagrams. These spore concentrations were presented using three curves for all, dry and rainy days in 1997–1999 (April–November). The spore percentage in particular hours was normalized in relation to the daily spore sum accepted as 100%. Two further diagrams enabled the more precise analysis of the highest concentrations in dry days. Daily Botrytis and Cladosporium spore concentrations did not show significant differences between dry and rainy periods. In the case of Didymella and Ganoderma spore concentrations, there were no significant differences between both weather types in the single years, although there was a significant difference when a 3-year period was considered. The differences between daily concentrations of Alternaria spores in dry and rainy periods occurred in 1997 and in a 3-year period. Intradiurnal periodicity of spore concentrations was different for ‘dry’ and ‘wet’ fungal spores. Dry spores are released from the spore-producing parts of the fungus under conditions of decreasing humidity and increasing airflow. Examples of dry spores are those from Alternaria, Cladosporium and Botrytis. Wet spores, such as those from many Ascomycetes (Didymella) and Basidiomycetes (Ganoderma), are released into the atmosphere by processes related to humidity conditions or rain. The highest concentrations of ‘dry’ spores were observed early in the afternoon, while highest values of ‘wet’ spore concentrations occurred in the predawn hours. Statistically non-significant differences between daily spore concentrations in dry and rainy periods of single seasons were found except for Alternaria. Statistically significant differences could occur when the studied period was longer than one season (Alternaria, Didymella, Ganoderma). The highest concentrations of Alternaria, Botrytis and Cladosporium spores were recorded at noon and early in the afternoon. Concentrations of Didymella and Ganoderma spores were highest in the predawn hours.     

Ecological characterization of coral growth anomalies on Porites compressa in Hawai��i

Bulbous skeletal structures with associated aberrant corallites have been abundant on Porites compressa in Kāne‘ohe Bay, O‘ahu, Hawai‘i, for at least the last 19 years. These growth anomalies (GA) appear in the summer in shallow (<3 m) water on some, but not on all colonies. GA-free branches, collected from colonies with GAs, produced GAs when cultured in outdoor flow-thru aquaria. Normal branches, whose tissues were continuous with those of GAs, grew in length much more slowly than normal branches from the same colony that were not connected with a GA, suggesting that there is a translocation of materials from normal tissue to GAs. Small experimental colonies that were either exposed to, or protected from, UV radiation did not differ in their rate of GA formation. GAs had a lower probability of survival than normal branches. This characteristic, in combination with their effect on the growth of normal branches and other reported deficiencies in the tissues of growth anomalies (e.g., reduced or failed reproduction), suggests that GA-bearing colonies of this species have reduced fitness.     

Convergent evolution of the Dufour’s gland secretion as a propaganda substance in the slave-making ant genera Protomognathus and Harpagoxenus

Slave-making ants are social parasites which exploit the workforce of heterospecific slaves for their own reproduction, and to this end they have developed a variety of morphological and behavioural adaptations. Furthermore, social parasites utilize the chemical communication system of their hosts by breaking their nestmate recognition code, and some slave-maker species additionally employ semiochemicals as weapons during colony foundation and slaveraiding. Here, we demonstrate the use of such a ‘propaganda allomone’ by the North American myrmicine slave-maker Protomognathus americanus. This substance is produced in the Dufour’s gland and may be employed during slave raids to elicit panic among defending host workers. Slave-maker Dufour’s gland secretions evoked agitation and heightened levels of activity among host workers when applied directly on a host nest, and strong aggressive responses of nestmates when applied onto a host worker. Although the hosts own Dufour’s gland secretion also elicits intra-colonial fights, no support for the hypothesis was found that the slave-maker propaganda substance mimics a fertility signal of the host, as the chemical profile of the gland secretions is highly divergent between the two species. Preliminary results on the chemical composition of the secretion obtained by gas chromatography indicate that the propaganda substance of P. americanus differs from that of the related European slavemaker Harpagoxenus sublaevis, and is thus likely to represent an independent evolutionary development. Received 24 February 2005; revised 28 July 2005 and 2 March 2006; accepted 6 March 2006.     

Crossing fitness valleys during the evolution of limpet homing behaviour

Evolution is often considered a gradual hill-climbing process, slowly increasing the fitness of organisms. Here I investigate evolution of homing behaviour in simulated intertidal limpets. While the simulation of homing is only a possible mechanism by which homing may have evolved, the process allows an investigation of how evolution may occur over different fitness landscapes. With some fitness landscapes, in order to evolve path integration as a homing mechanism, a temporary reduction in an organism’s fitness was required — since high developmental costs occurred before successful homing strategies evolved. Simple hill-climbing algorithms, therefore, only rarely resulted in the evolution of a functional homing behaviour. The inclusion of trail-following greatly increases the frequency of success of evolution of a path integration strategy. Initially an emergent homing behaviour is formed combining path integration with trail-following. This also demonstrates evolution through exaptation, since in the simulation, the original role of trail-following is likely to be unrelated to homing. Analysis of the fitness landscapes of homing in the presence of trail-following behaviour shows a high variability of fitness, which results in the formation of ‘stepping-stones’ of high fitness across fitness valleys. By using these stepping-stones, simple hill-climbing algorithms can reach the global maximum fitness value.     

Assessing the validity of impact pathways for child labour and well-being in social life cycle assessment

Background, aim and scope  

Assuming that the goal of social life cycle assessment (SLCA) is to assess damage and benefits on its ‘area of protection’ (AoP) as accurately as possible, it follows that the impact pathways, describing the cause effect relationship between indicator and the AoP, should have a consistent theoretical foundation so the inventory results can be associated with a predictable damage or benefit to the AoP. This article uses two concrete examples from the work on SLCA to analyse to what extent this is the case in current practice. One considers whether indicators included in SLCA approaches can validly assess impacts on the well-being of the stakeholder, whereas the other example addresses whether the ‘incidence of child labour’ is a valid measure for impacts on the AoPs.     

Improvement of isolated microspore culture of pepper (<Emphasis Type="Italic">Capsicum annuum</Emphasis> L.) via co-culture with ovary tissues of pepper or wheat

The influence of the developmental stage of microspores on establishing isolated microspore cultures of three Hungarian (‘Szegedi 80’, ‘Szegedi 178’, and ‘Remény’) and three Spanish (‘Jeromin’, ‘Jariza’, and ‘Jaranda’) pepper genotypes was investigated. Donor anthers containing 80% uninucleated and 20% binucleated microspores yielded the highest frequency of successful microspore cultures. Co-cultures with wheat, line ‘CY-45’, ovaries exhibited enhanced frequency of embryoid production than those with pepper ovaries. Differences in efficiency of isolated pepper microspore culture establishment were observed among different pepper genotypes. Green plantlets were regenerated from microspore-derived embryoids, but some were exhibited abnormal growth habits, such as leaf rosetting. A total of seven fertile microspore-derived plants were obtained, including three ‘Jariza’, three ‘Jaranda’, and a single ‘Szegedi 80’ plant.     

What is the appropriate timescale for measuring costs of reproduction in a `capital breeder' such as the aspic viper?

Before we can quantify the degree to which reproductive activities constitute a cost (i.e., depress an organism's probable future reproductive output), we need to determine the timescale over which such costs are paid. This is straightforward for species that acquire and expend resources simultaneously (income breeders), but more problematical for organisms that gather resources over a long period and then expend them in a brief reproductive phase (capital breeders). Most snakes are capital breeders; for example, female aspic vipers (Vipera aspis) in central western France exhibit a 2- to 3-year reproductive cycle, with females amassing energy reserves for one or more years prior to the year in which they become pregnant. We use long-term mark-recapture data on free-living vipers to quantify the appropriate timescale for studies of reproductive costs. Annual survival rates of female vipers varied significantly during their cycle, such that estimates of survival costs based only on years when the females were ‘reproductive’ (i.e., produced offspring) substantially underestimated the true costs of reproduction. High mortality in the year after reproducing was apparently linked to reproductive output; low energy reserves (poor body condition) after parturition were associated with low survival rates in the following year. Thus, measures of cost need to consider the timescale over which resources are gathered as well as that over which they are expended in reproductive activities. Also, the timescale of measurement needs to continue long enough into the post-reproductive period to detect delayed effects of reproductive ‘decisions’. This revised version was published online in July 2006 with corrections to the Cover Date.     

Multimodality molecular imaging of disease progression in living subjects

The enormous advances in our understanding of the progression of diseases at the molecular level have been supplemented by the new field of ‘molecular imaging’, which provides for in vivo visualization of molecular events at the cellular level in living organisms. Molecular imaging is a noninvasive assessment of gene and protein function, protein–protein interaction and/or signal transduction pathways in animal models of human disease and in patients to provide insights into molecular pathogenesis. Five major imaging techniques are currently available to assess the structural and functional alterations in vivo in small animals. These are (i) optical bioluminescence and fluorescence imaging techniques, (ii) radionuclide-based positron emission tomography (PET) and single photon emitted computed tomography (SPECT), (iii) X-ray-based computed tomography (CT), (iv) magnetic resonance imaging (MRI) and (v) ultrasound imaging (US). Functional molecular imaging requires an imaging probe that is specific for a given molecular event. In preclinical imaging, involving small animal models, the imaging probe could be an element of a direct (‘direct imaging’) or an indirect (‘indirect imaging’) event. Reporter genes are essential for indirect imaging and provide a general integrated platform for many different applications. Applications of multimodality imaging using combinations of bioluminescent, fluorescent and PET reporter genes in unified fusion vectors developed by us for recording events from single live cells to whole animals with high sensitivity and accurate quantification are discussed. Such approaches have immense potential to track progression of metastasis, immune cell trafficking, stem cell therapy, transgenic animals and even molecular interactions in living subjects.