In our solar system, an asteroid orbits the Sun in the opposite direction to the planets. It takes 12 years to make one complete orbit around the Sun. The asteroid with the retrograde co-orbit was identified by Helena Morais, a professor at São Paulo State University's Institute of Geosciences & Exact Sciences, in Brazil. In partnership with Fathi Namouni at the Côte d'Azur Observatory in France, Morais developed a general theory on retrograde co-orbitals and retrograde orbital resonance.

When both partners benefit from a relationship -- husband and wife or pollinator and flower -- the relationship is known as a mutualism. Sometimes partners do not deliver their side of the bargain while still reaping the rewards. Research done at the Smithsonian in Panama published shows that unless unfaithful partners are severely punished by the other member of the relationship cheaters may become more common.

Vines compete intensely with trees. Their numbers are on the rise in many tropical forests around the world. A new study at the Smithsonian Tropical Research Institute in Panama shows that lianas prevent canopy trees from producing fruit, with potentially far-reaching consequences for rainforest animals.

A group of researchers at the University of Campinas's Biology Institute (IB-UNICAMP) in São Paulo State, in collaboration with colleagues at the Agronomy Institute (IAC) and at the University of São Paulo's Chemistry Institute (IQ-USP), have discovered how chemical ripeners, which are analogous to plant hormones, act on the molecular level in sugarcane to increase sucrose storage in the plant.

Researchers at the University of Campinas's Gleb Wataghin Physics Institute (IFGW-UNICAMP) in São Paulo State, Brazil, have theoretically developed a silicon photonic device with a diameter of approximately 10 microns (μm), equivalent to one tenth of the thickness of a human hair, that would enable optical and mechanical waves vibrating at tens of gigahertz (GHz) to interact.

Researchers at São Paulo State University (UNESP) in Brazil have published a census of medium and large mammals found in 22 forest remnants surrounded by sugarcane plantations in the state. They found approximately 90 percent of all the species of mammals expected for São Paulo State but in smaller forest fragments, the researchers recorded only 20 percent - 50 percent of the species expected to occur across the region. This means that up to 80 percent were locally extinct in some cases.

Study offers new theoretical approaches to explain and predict high-energy nuclear collisions experiments; Computer simulations performed enabled the researchers to make predictions to test, validate or correct the model.

Likely the first bone tumor from an ancient skeleton in Central America is reported by Smithsonian archaeologists and colleagues. The starburst-shaped tumor is in the upper right arm of the skeleton of an adolescent buried in about 1300 AD in a trash heap at a site in western Panama called Cerro Brujo or Witch Hill. The reason for what appears to be a ritual burial in this abandoned pre-Colombian settlement is unknown.

Ninety Limosa harlequin frogs (Atelopus limosus) bred in human care are braving the elements of the wild after Smithsonian scientists sent them out into the Panamanian rainforest as part of their first-ever release trial in May. The study, led by the Panama Amphibian Rescue and Conservation Project, aims to determine the factors that influence not only whether frogs survive the transition from human care to the wild, but whether they persist and go on to breed.