Hummingbirds - elegant and light? Not all of them! Of approximately 340 species of hummingbirds, 70% weigh six grams or less, while 30% weigh between six and ten grams. The giant hummingbird, Patagona gigas, with its 20g, is a heavy weight! Other animal species, rodents for example, contain individuals ranging in body mass from 10 grams to a rather phenomenal 60 kilograms. However, unlike the hummingbird, these mass differences occur gradually, rather than with a large ‘gap’ of mass. Maria Jose Fernandez from University of California, Berkeley, will be presenting her work trying to unravel the secret of P. gigas’ extreme size at the SEB meeting at the Universitat Autonoma de Barcelona on Tuesday 12th of July.
The giant hummingbird can be found in countries such as Ecuador and Chile, where Fernandez is investigating the upper limit, which could explain the upper body size among hummingbirds. She measured the influence of energy use and nutrient uptake on the birds’ hovering flight style, a mechanism which is in some ways similar to that of helicopters. Hovering is highly demanding, displaying some of the highest mass specific rates of aerobic metabolism and muscle power output among vertebrates. No difference was seen between the maximum metabolic rate and the daily energy expenditure, which means that the basal metabolic rate is the influential factor for the size of the hummingbird. “It is not unreasonable to suggest that there are energetic constraints on the evolution of body size”, says Fernandez.
Diana van Gent | alfa
Water forms 'spine of hydration' around DNA, group finds
26.05.2017 | Cornell University
How herpesviruses win the footrace against the immune system
26.05.2017 | Helmholtz-Zentrum für Infektionsforschung
Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.
Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....
Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.
The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....
An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.
We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...
Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.
Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...
An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...
24.05.2017 | Event News
23.05.2017 | Event News
22.05.2017 | Event News
26.05.2017 | Life Sciences
26.05.2017 | Life Sciences
26.05.2017 | Physics and Astronomy