madame scientist's not-so-mad musings

Interstellar Overdrive: Take the Milky Way Transit Authority.

Samuel Arbesman, a postdoctoral fellow in computational sociology at Harvard, made this simplified map of the Milky Way. Just take the Tube.

He says, “People ask why I haven’t marked ‘You Are Here’ on the map – but I think it’s more humbling to realize that we aren’t the center of the universe.” http://arbesman.net/milkyway/

Pink Floyd With Syd Barrett – Interstellar Overdrive-Part 1

#scienceeveryday   Samuel Arbesman 

Fish With Transparent Head Filmed 

This barrel eye fish is not going to win any beauty prizes. But it surely deserves admiration for its enormous telescoping eyes, housed in a transparent head that functions as a muscle-driven lens to scavenge what little light penetrates the inky ocean depths. The huge green lenses points to a retina with exceptional density of rod cells, packed with the light harvesting protein rhodopsin.  Cone cells, that see color, are absent. Those two tiny openings on either side of its mouth? They are nostrils .

The fish spends most of its time motionless, eyes directed upwards to catch the shadow of prey emitting faint bioluminescence.

#scienceeveryday when it’s not ScienceSunday .

Sweet Memories: Do you recall what you had for dessert at your last dinner party? I’m sure you would remember the hippocampus cookies (left image)! The hippocampus (right image) is the part of our brain responsible for episodic memory, the kind associated with a great dinner surrounded by family or friends. It enables you to “play back” the memories, until eventually the memory becomes ingrained in the cortex.

• The hippocampus is also important for spatial memory: in one study, British researchers asked taxi drivers to imagine their routes through London while their brain activity was scanned by positron emission tomography (PET scan). This task specifically activated the right lobe of the hippocampus. There are other types of memory that do not involve the hippocampus: semantic memory, for general knowledge (frontal and temporal cortex), emotional memory such as fear (amygdala), and procedural memory, such as knowing how to ride a bike (cerebellum, motor cortex).

• In Alzheimer’s disease, the hippocampus is the first, and most severely, affected part of the brain. That’s why new memories are the first to go: Where did I put the car keys?  Why is there no mail today (because you just brought it in).

• The distinct curves of the hippocampus region of the vertebrate brain has been likened to a sea horse (genus Hippocampus) from Greek mythology, and the horns of the ram Amun, in Egyptian mythology. The latter name is the basis for four regions, designated CA1-4, after Cornu Ammonis or the horns of Amun.

Remember to tag your posts #scienceeveryday when it’s not ScienceSunday 🙂

Blowing in the Wind: Ever wonder how a pollinating insect clings to flower petals even in the face of a stiff wind? A close look would show their feet firmly grasped by velcro like surface of conical cells (left image). Since the cells are about the same size as the tiny claws on bees’ feet, the claws slide in between the cones for a tight grip. This special doormat is only found in flower petals and nowhere else on the plant.

• University of Cambridge scientist Beverly Glover offered bees Petunias either with conical cells on their petals, or a mutant flat variety. At first, the bees showed only a slight preference for the flowers with conical cells. But when she simulated a wind by placing the flowers on a laboratory shaker (nicely covered in green tissue paper, right image), the bees clearly preferred the conical cells. Even if they had a choice of preferred color (they like the lighter Petunias better), they chose the grippy petals. This is an extraordinarily subtle interaction between a flower and pollinator!

• Why is it that some 20% of flowers (tulips, magnolias, lilies) have smooth, flat petals? Scientists speculate this may be because they are pollinated by hummingbirds or hovering insects that have no use for the sticky landing pad. 

REF: Alcorn, K., Whitney, H., & Glover, B. (2012). Flower movement increases pollinator preference for flowers with better grip Functional Ecology DOI: 10.1111/j.1365-2435.2012.02009.x

Blowin’ in the wind – Bob Dylan

#scienceeveryday