Source: NOAA Alaska Fisheries Science Center MESA Project
“Microscopic phytoplankton floating in the upper layers of the ocean use the sun’s energy to photosynthesize carbohydrates. These carbohydrates can be eaten for energy, and these plants - mostly diatoms and algae - are the foundation of the majority of the ocean’s biological community. In areas of the ocean where there is not light, some producers can even create energy by using the process of chemosynthesis instead of photosynthesis.”
(via scinerds)
The Cell’s Muscles and Bones
Cell movement begins with lamellipodia. A thin sheet of actin filaments (light purple) that stretches out to the cell’s periphery, lamellipodia generate pushing forces that drive the cell forward. Microtubules (cyan) can barely penetrate this actin network, but they direct cell motility in other ways, such as controlling cell adhesion and acting as the cell’s internal compass.
Image: A human HaCat keratinocyte responds to epidermal growth factor by rapidly forming a lamellipod around most of its perimeter. The cell was fixed and processed within minutes after EGF addition. F-actin is stained with fluorescently labeled phalloidin (light purple), and microtubules are labeled with an antibody (cyan). DNA dye stains the nucleus dark purple.
smallest chameleon in Madagascar!
(Source: chopstickgirl, via imgfave)
Evolution Is Written All Over Your Face
Why are the faces of primates so dramatically different from one another? A very interesting study that examines the differences in faces amongst New World primates.
Humans have pretty bare faces, which may allow us to see facial expressions more easily than if, for example, we had many colors in our faces.
This finding suggests that facial expressions are increasingly important in large groups. If you’re highly social, then facial expressions matter more than having a highly complex pattern on your face.
New research that includes representatives of 99% of mammalian families, has provided a ‘big picture’ for mammalian phylogeny. By assembling a large and robust DNA matrix, based on sequences of many different genes, a research team led by biologists from the University of California, Riverside and Texas A&M, has examined how different families are related to each other.
Based on this data, the team was able to construct evolutionary trees (see figure 1) and date divergence times. These divergence dates were estimated with the help of a relaxed molecular clock, allowing the team to incorporate different rates of evolution, rather than just one. The tree was calibrated with age estimates of numerous mammalian fossils. This research is meant to be a starting point for further inquiry, such as developing trees that incorporate representatives for genera and species. (via Improving Understanding Of Mammal Evolution)
(via science-stuff)
Neanderthal sex boosted immunity in modern humans »
Sexual relations between ancient humans and their evolutionary cousins are critical for our modern immune systems,researchers report in Science journal.
A theme in evolutionary and developmental biology (“evo-devo”) is that patterns of gene expression in early stages of development (left column) reflect forms in later in development (right column). This theme is illustrated by a fruit fly embryo vs. a later-stage fruit fly larva (top row); and a developmental form of a butterfly wing vs. an adult butterfly wing (bottom row).
coooooool! ;)
