Brood recognition and discrimination in ants

In social insect colonies, individuals need to communicate to coordinate cooperative tasks and protect the colony and its resources against intruders. To maintain colony integrity, it can be particularly important to recognize nestmates and discriminate against non-nestmate conspecifics and heterospecific predators and parasites. As typical intruders are either con- or heterospecific adults, the mechanisms underlying recognition and discrimination processes in interactions among adults have been well described. Ant brood (eggs, larvae, and pupae) can also play a key role in social interactions, and brood is of special importance when it comes to the priorities of worker ants. However, whether ants can, or even need to, recognize brood of different origins, is not always clear. In this review, we integrate the results of 100 years of study on brood recognition and discrimination in ants into a general framework. We begin with an overview of the proximate mechanisms involved in brood recognition and discrimination. We then discuss why brood recognition and discrimination should evolve and review the evidence for brood recognition on three organizational levels: within nests, between conspecifics and between species. We conclude by examining the constraints acting on accurate recognition and/or discrimination. With this review, we hope to inspire future research on the fascinating life of ant brood.Peer reviewe

Sized-related changes in winter condition of male calves in reindeer

Size-related changes in body condition of free-ranging male calves of semi-domesticated reindeer were studied in northern Finland from October 1983 to February 1984. In October-November, back fat depth or muscle fat percent correlated positively with the body size (=back length). In January, the highest means especially for muscle fat percent were found among medium-sized calves. Carcass weight and weight/back length ratio correlated positively with size, excluding February sample, where correlation for carcass weight was non-significant and for weight/back length ratio negative. Weight in the autumn correlated negatively with weight in February. Therefore, normalizing selection for body size (working against small and large phenotypes) is expected to occur in late winter. Small calves may be at greater mortality risk because of lower initial body reserves. Large calves commonly disperse during the rutting season and they may suffer most from increased food competition later in winter. Using of medium-sized calves for breeding might be the safest policy on ranges characterized by short food supply and difficult snow conditions.Koon vaikutus poron urosvasojen talviseen kuntoon.Abstract in Finnish / Tiivistelmä: Koon vaikutusta vapaana laiduntavien poron urosvasojen kuntoon tutkittiin Pohjois-Suomessa loka-helmikuussa talvella 1983-84. Loka-marraskuussa selkärasvan paksuus tai lihaksen rasvaprosentti riippui vasan koosta ( = selän pituus). Tammikuussa sen sijaan lihaksen rasvaprosentti oli korkein keskikokoisilla vasoilla. Ruhopaino sekä ruhopaino/selän pituus oli yleensa riippuvainen koosta. Helmikuussa ruhopainon riippuvuus koosta ei ollut enää tilastollisesti merkitsevä, ja koon ja ruhopainon/selänpituuden välinen korrelaatio oli negatiivinen. Eniten painoa menettivät (%) loka-helmikuun välillä suurikokoisimmat vasat. Havainnot viittaavat siihen, että talvella esiintyvä kuolleisuus on normalisoivaa koon suhteen (karsii pieniä ja suuria fenotyyppejä). Pienten vasojen kuolleisuusriski on suuri alunperinkin vähäisen varastoravinnon vuoksi. Suuret vasat puolestaan erkaantuvat usein emistään jo rykimäaikana, ja joutuvat kärsimään eniten talven mittaan kiristyvästä ravintokilpailusta. Niukoilla laitumilla siitokseen on turvallisinta säästää keskikokoisia vasoja.Sammenhengen mellom størrelse og vinterkondisjon hos hankalver av reinsdyr.Abstract in Norwegian / Sammendrag: Størrelses-relaterte forandringer i kroppskondisjon hos fritt beitende han-kalver av semidomestiserte rein er studert i Nord-Finland fra oktober 1983 til februar 1984. I oktober - november korrelerte tykkelsen av ryggfettet eller muskelfett-prosenten positivt med kroppsstørrelsen (= rygglengden). I januar ble de høyeste middelverdier, særlig for muskelfett-prosenten, funnet hos kalver av middels størrelse. Skrott-vekter og vekt/rygglengde-forholdet korrelerte positivt med kroppsstørrelse bortsett fra februar-prøvene, der korrellasjonen for skrott-vekt var ikke-signifikant og for vekt/rygglengde-forholdet var negativt. Vekt om høsten korrelerte negativt med vekt i februar. Derfor ventes et normaliserende utvalg for kroppsvekt (som arbeider mot små og store fenotyper) å skje på senvinteren. Små kalver er utsatt for større dødsrisiko på grunn av lavere kroppsreserver. Store kalver streifer vanligvis under brunsttiden og kan komme til å lide under økt næringskonkurranse på senvinteren. Bruk av middels store kalver i avlen kan være den sikreste metode på beiter som karakteriseres av dårlige næringstilgang og vanskelige snøforhold

The familiar area hypothesis and movement patterns of wild forest reindeer in Karelia, Northern Europe

The relevance of the familiar area hypothesis to the behaviour of the wild forest reindeer (Rangifer tarandus fennicus Lönnb.) was studied in a Fenno-Soviet project by radio and field tracking of these ungulates in Karelia, Northern Europe, in 1978 - 1985. This subpopulation (500 - 600 exx.) has a tradition of overwintering in a restricted area around Lake Lentua (ca. 1000 km2). The spring migration period is shorter in length than the autumn migration. The migration routes are generally the same in autumn and spring, although exceptions occur, indicating exploratory behaviour. The large winter herds disband into small groups or lone individuals for the summertime, when this subpopulation is spread over a much wider area (ca. 5400 km2). It is concluded that the observations made support the familiar area hypothesis in all essential points

Dynamics of a host–parasitoid interaction clarified by modelling and DNA sequencing

Abstract It has been hypothesised that the 2-year oscillations in abundance of Xestia moths are mediated by interactions with 1-year Ophion parasitoid wasps. We tested this hypothesis by modelling a 35-year time series of Xestia and Ophion from Northern Finland. Additionally, we used DNA barcoding to ascertain the species diversity of Ophion and targeted amplicon sequencing of their gut contents to confirm their larval hosts. Modelling of the time-series data strongly supported the hypothesised host?parasitoid dynamics and that periodic occurrence of Xestia moths is mediated by Ophion. DNA barcodes revealed that Ophion included five species rather than just one while targeted amplicon sequencing verified that Ophion does parasitise Xestia. At least one Ophion species employs 1-year Syngrapha interrogationis as an alternate host, but it did not detectably affect Xestia?Ophion dynamics. We also demonstrate the previously unrecognised complexity of this system due to cryptic parasitoid diversity.peerReviewe

Experiences of interactive ultrasound examination among women at risk of preterm birth: a qualitative study

Background: Pregnant women who are at risk of preterm birth are often stressed, anxious and depressed because of worries and fears related to the health of the unborn baby, their own health and uncertainty about the future. Only a few studies have assessed the types of psychological support that would relieve these stress symptoms among women with high-risk pregnancies. The aim of this study was to describe 1) how women at risk of preterm birth experienced an interactive 3/4-dimensional (3/4D) ultrasound examination, and 2) their need for psychological support during the antenatal period.Methods: This qualitative study was conducted at one university hospital in Finland in 2017. Women with a singleton pregnancy of 26-32 gestational weeks (gwks) were included in the study. The interactive 3/4D ultrasound included a joint observation of the baby, based on the mother's wishes, with an obstetrician and psychologist. After the examination, the experiences were explored with a semi-structured interview. The data was analyzed using inductive thematic analysis.Results: The women enjoyed the fact that the staff were focused on her fetus and genuinely present during the session and also enabled the women to actively participate. Watching the baby and her/his activities made the baby more concrete and relieved their concerns. The need for additional psychological support varied individually.Conclusions: Interactive ultrasound examination is an interesting way to awaken mental images, increase attachment, and reduce stress. The results imply that an interactive way of jointly looking at the fetus supports pregnant women at risk of preterm birth and may be useful in clinical practice.</p

Different responses of colorectal cancer cells to alternative sequences of cetuximab and oxaliplatin

Therapeutic protocols including EGFR antibodies in the context of oxaliplatin-based regimens have variable clinical effect in colorectal cancer. Here, we tested the effect of the EGFR antibody cetuximab in different sequential combinations with oxaliplatin on the growth of colorectal cancer cells in vitro and in vivo. Cetuximab reduced the efficacy of oxaliplatin when administered before oxaliplatin but provided additive effect when administered after oxaliplatin regardless of the KRAS or BRAF mutation status of the cells. Systemic gene expression and protein phosphorylation screens revealed alternatively activated pathways regulating apoptosis, cell cycle and DNA damage response. Functional assays indicated that cetuximab-induced arrest of the cells into the G1 phase of the cell cycle was associated with reduced responsiveness of the cells to subsequent treatment with oxaliplatin. In contrast, oxaliplatin-enhanced responsiveness to subsequent treatment with cetuximab was associated with increased apoptosis, inhibition of STAT3 activity and increased EGFR down-regulation. This preclinical study indicates that optimizing the sequence of administration may enhance the antitumor effect of combination therapy with EGFR antibodies and oxaliplatin

Winter Bird Assemblages in Rural and Urban Environments: A National Survey

Urban development has a marked effect on the ecological and behavioural traits of many living organisms, including birds. In this paper, we analysed differences in the numbers of wintering birds between rural and urban areas in Poland. We also analysed species richness and abundance in relation to longitude, latitude, human population size, and landscape structure. All these parameters were analysed using modern statistical techniques incorporating species detectability. We counted birds in 156 squares (0.25 km2 each) in December 2012 and again in January 2013 in locations in and around 26 urban areas across Poland (in each urban area we surveyed 3 squares and 3 squares in nearby rural areas). The influence of twelve potential environmental variables on species abundance and richness was assessed with Generalized Linear Mixed Models, Principal Components and Detrended Correspondence Analyses. Totals of 72 bird species and 89,710 individual birds were recorded in this study. On average (±SE) 13.3 ± 0.3 species and 288 ± 14 individuals were recorded in each square in each survey. A formal comparison of rural and urban areas revealed that 27 species had a significant preference; 17 to rural areas and 10 to urban areas. Moreover, overall abundance in urban areas was more than double that of rural areas. There was almost a complete separation of rural and urban bird communities. Significantly more birds and more bird species were recorded in January compared to December. We conclude that differences between rural and urban areas in terms of winter conditions and the availability of resources are reflected in different bird communities in the two environments

Global snow mass measurements and the effect of stratigraphic detail on inversion of microwave brightness temperatures

Snow provides large seasonal storage of freshwater, and information about the distribution of snow mass as Snow Water Equivalent (SWE) is important for hydrological planning and detecting climate change impacts. Large regional disagreements remain between estimates from reanalyses, remote sensing and modelling. Assimilating passive microwave information improves SWE estimates in many regions but the assimilation must account for how microwave scattering depends on snow stratigraphy. Physical snow models can estimate snow stratigraphy, but users must consider the computational expense of model complexity versus acceptable errors. Using data from the National Aeronautics and Space Administration Cold Land Processes Experiment (NASA CLPX) and the Helsinki University of Technology (HUT) microwave emission model of layered snowpacks, it is shown that simulations of the brightness temperature difference between 19 GHz and 37 GHz vertically polarised microwaves are consistent with Advanced Microwave Scanning Radiometer-Earth Observing System (AMSR-E) and Special Sensor Microwave Imager (SSM/I) retrievals once known stratigraphic information is used. Simulated brightness temperature differences for an individual snow profile depend on the provided stratigraphic detail. Relative to a profile defined at the 10 cm resolution of density and temperature measurements, the error introduced by simplification to a single layer of average properties increases approximately linearly with snow mass. If this brightness temperature error is converted into SWE using a traditional retrieval method then it is equivalent to ±13 mm SWE (7% of total) at a depth of 100 cm. This error is reduced to ±5.6 mm SWE (3 % of total) for a two-layer model