Previous studies of hair loss have identified signals from the skin that help prompt new phases of hair growth and a new study reveals a new way to spur hair growth. 

Today is the day when a whole lot of people will be exchanging gifts that don't fit or they don't want, and maybe buying something they did want.

It's the perfect time to think about gift exchanges. Gift exchanges can reveal how people think about others, what they value and enjoy, and how they build and maintain relationships. Researchers are exploring various aspects of gift-giving and receiving, such as how givers choose gifts, how gifts are used by recipients, and how gifts impact the relationship between givers and receivers. 

 Edentulism, the absence of teeth, has evolved on multiple occasions within vertebrates including birds, turtles, and a few groups of mammals such as anteaters, baleen whales and pangolins, but where early birds are concerned, the fossil record is fragmentary.

A question that has intrigued biologists is whether teeth were lost in the common ancestor of all living birds or convergently in two or more independent lineages of birds.

A research team using the degraded remnants of tooth genes in birds to determine when birds lost their teeth believes that teeth were lost in the common ancestor of all living birds more than 100 million years ago.

Enzymes are crucial for assisting virtually all biological processes, but there has been little consensus on how they work. Molecular processes crucial to life are made possible by these but beyond that less is known. 

Chemists looking inside a working enzyme have found that local electric fields focused at the active site might play a big role in helping it accelerate reactions. The electrostatic field within an enzyme accounts for the lion's share of its success, they conclude.

Internet addiction, an impulse-control problem marked by an inability to inhibit Internet use, can adversely affect a person's life, including their health and interpersonal relationships. The prevalence of Internet addiction varies among regions around the world, as shown by data from more than 89,000 individuals in 31 countries analyzed for a study published in Cyberpsychology, Behavior, and Social Networking.

The distinctive "fecal prints" of microbes could provide a record of how Earth and life have co-evolved over the past 3.5 billion years as the planet's temperature, oxygen levels, and greenhouse gases have changed but it's been difficult to decipher much of the information contained in this record.

A new project sheds light on the mysterious digestive processes of microbes, opening the way towards a better understanding of how life and the planet have changed over time. Using a new technique, researchers  focused on the microbes that live on the ocean floor where the microbes consume the sulfate found in seawater because oxygen is in short supply.