Stammering, stuttering or alalia literalis is a speech disorder characterized by involuntary repetition and prolongations of sounds, syllables, words or phrases and involuntary silent pauses or blocks where the affected person is unable to produce sounds. Around 1-in-20 children aged 2 to 5 years old will stammer at some moment, but most grow out of […]
Biology • Biomedicine • Health • Medicine
What are lysosomes doing inside your cells? When I was in High School my teacher used to say that lysosomes are only the trash bin of the cell. 20 years later we have discovered a dozen new functions that make this small organelle a core component of the cell. You may already know that the […]
Anthropology • Biology • Evolution • Genetics
Neanderthals ( Homo neanderthalensis ) were a species –some say a subspecies although most authors consider there is enough evidence to consider them as a separate species– of human closely related to us. They were firstly discovered in a cave in the Neander Valley («Tal» in German), about 12 km east of Düsseldorf. There is […]
Hibernation is a state of inactivity and metabolic depression used by some mammals to survive a cold winter. It may last several days, weeks, or months depending on the species, environment temperature, season, and individual’s body condition. Usually, hibernating animals survive the energetic bottleneck of the winter by building stores of body fat in late […]
In multicellular organisms, embryonic stem cells develop into any of the different cell types that will form the adult, and along the development, they silence or activate different parts of the genome, giving rise to distinct cell identities, which are maintained throughout adult life by epigenetic mechanisms. A similar procedure may be at work at […]
One hears blue blood and immediately thinks about royal family members. Some biologists, though, immediately will think about Limulus polyphemus , a marine animal commonly known as the horseshoe crab. Why? Because, very surprisingly, this arthropod actually has true blue blood! Human blood is red because of the hemoglobin inside our red blood cells, which […]
Behavioral lateralization is a significant field of study because it may provide insights into the initial origins of lateralization. Different and very diverse organisms show lateralization. The best known is handedness, a better (faster or more precise) performance or individual preference for use of a hand but it is not unique, many creatures, including humans […]
Complex systems in biology have several levels of organization, establishing a hierarchy of systems and subsystems. An ant colony is a wonderful example with the highest level being the colony itself, formed by hundreds or thousands of insects, each individual ant formed by millions of cells including 10 5 -10 6 neurons, and each cell […]
Animals drift when they enter a fluid (liquid or gas) and are transported to a new location by gravity or currents. Drift is best known from rivers and ocean currents, but can also occur on land, whenever organisms leave their former solid position, pass into the air, and are moved significant distances by the combined […]
The biological world is composed of dense, communicating, and difficult to understand ensembles. Animals living in groups –a school of fish, a flock of birds– have evolved to act in concert, a quality needed for coordinated movement. More complex than just moving together, group carrying is fairly rare in nature and only social spiders, dung […]