By Sareh

Eurasian Jay

During our walk in nature, I came across the Eurasian Jay; the most colorful of the crow family and a very adaptable and successful species that has spread throughout the greater parts of europe and asia. 

It has a couple very fascinating features, one of them being its ability to mimic sounds of all sorts. Upon being attacked it mimics the sound of its predator, spreading confusion, but it also alarms fellow members of predators. This is why the Eurasian Jay is sometimes called the "police man of the forrest".

This little bird also plays an important role in the regeneration of oak trees. One bird hides as many as 4500- 11,000 acorns per year. It rarely every hides more than one acorn per spot, and it can spread them up to distances of about 3km. Some of these acorns are lost or forgotten, which then leads to the regeneration of oak trees far away from the mother tree. It is estimated that the "work" done by this little bird, in Sweden alone, is worth many millions every year.  

by Mikaela Grassl

Walking in Nature

Some picuters!

Architecture that mimics the snail

Last weekend I was in Lebanon skiing. I got a little interested in the area, and decided to dig deeper into biomimicry and architecture in the middle east. I came across this proposal by a group of Iranian Students. This proposal actually won a student competition hosted by the Biomimicry Institute earlier this spring. The design takes its inspiration from the snail, which has remarkable qualities that allows it to stay both cool and moist in the most harsh temperatures. The aim of this desert building then was to be self-cooling - just like a snail. 

To mimic the curvature of the snail´s shell, the students created crescent shaped panels that overlap one another. These prevent excess sunlight from penetrating the interior and its off-white color is thought to reflect sunlight. Like the snail, which retreats far into the depths of its shell when the sun blazes, residents of this desert dwelling can escape the heat by tunneling further into the building´s recess. I think this is a fascinating idea. Rather that us always being in complete control of our surroundings, we learn how to cope with them.

Here is a link to the Biomimicry Institute and the student challenge:

http://biomimicrydesignchallenge.com/p/2011-winners

by mikaela grassl

Shadow cooling in rainforests

These are the slides from last week's class showing how sunlight gets filtered through the foliage in rainforests, and the effect it has on the temperature of the different strata of the forest.

// Satu

Webspinners' silk galleries

Webspinners (Embioptera order) are a small group of mostly tropical and subtropical insects. Their common name comes from the insects' ability to spin silk from structures on their front legs. They then use the silk to make a web-like pouch or gallery in which they live.

The silk is produced in spherical secretary glands in the tarsi of the insects' forelimbs, and can be produced by both adults and larvae. Some species of webspinners are estimated to have up to 300 silkglands: 150 in each forelimb. These glands are linked to 'setae-like cuticular process called a silk ejector', and their exceedingly high numbers allow individuals to spin large amounts of silk very quickly, creating extensive galleries. The silk web is produced throughout all stages of the webspinners lifespan, and requires very little energy output.

The ‘galleries' produced by webspinners are tunnels and chambers woven from the silk they produce. These woven constructions can be found on substrates such as rocks and the bark of trees, or in leaf litter. Some species camouflage their galleries by decorating the outer layers with bits of leaf litter or other materials to match their surroundings. The galleries are essential to their life cycle, maintaining moisture in their environment, plus offering protection from predators and elements while foraging, breeding and simply existing. The only occasion when an embiid will leave the gallery complex is when winged males fly out or wingless males walk out in search of a mate, or when females explore the area immediately surrounding them in search of a new food source. 

Webspinners continually extend their galleries into new food sources, and expand their existing galleries as they grow in size. The insects spin silk by moving their forelegs back and forth over the substrate, and rotating their bodies to create a cylindrical, silk-lined tunnel. Older galleries have multiple laminate layers of silk. Each gallery complex contains a number of individuals, often descended from a single female, and forms a complex maze-like structure, extending from a secure retreat into whatever vegetable food matter is available nearby. The size and complexity of the colony varies between species, and they can be very extensive in those species that live in hot and humid climates

How could this be applied to design? The webspinners' way of designing their galleries can be applied to designing larger-scale tensile structures, as they strive to minimize the use of material and produce the most effective structural forms.

You can experience a webspinner-like gallery yourself at Färgfabriken until next week. They have an interesting installation called TEJP Stockholm (Tape Stockholm) by Numen. 

The installation is a series of galleries hanging in the air, all made from clear packaging tape. Visitors can go inside the galleries and experience the atmosphere of the thin structure. 

Don't miss it, especially if you're going there for the miljonprogrammet Seminar tomorrow! It's super cool, fun and and educational at the same time! The installation closes on March 17th.

More information at: www.fargfabriken.se

Photos: Sara Mac Key via färgfabriken.se

// Satu

Wave energy technology inspired by kelp plants

BioWAVE is a technology inspired by the swaying motion of kelp plants in the ocean. Kelp are large seaweeds that grow vertically from the ocean floor, and constantly sway in the water. The BioWAVE system is designed to mimic these plants.

Photo source: http://geog.ucsb.edu/mobile/events/department-news/

The BioWAVE is mounted on the seafloor, with a pivot near the bottom. The array of buoyant floats, or "blades", interacts with the rising and falling sea surface (potential energy) and the sub-surface back-and-forth water movement (kinetic energy). As a result, the pivoting structure sways back-and-forth in tune with the waves, and the energy contained in this motion is converted to electricity by an onboard self-contained power conversion module. The conversion module contains a hydraulic system that converts the mechanical energy from this motion into fluid pressure, which is used to spin a generator. Power is then delivered to shore by a subsea cable. You can read more about BioWAVE here.

// Satu