Branching In Nature

BRANCHING!

• Balance of forces• Indicates flow of energy and/or materials • Efficient distribution and collection in

biological systems: roots, leaves, twigs, branches, bronchi, nervous system, circulatory system, hyphae

Branching patterns in nature are the result of a balance of forces. Branching patterns are an efficient way to distribute materials and energy

Distribution of Energy and materials!

Arial photograph of the Colorado River delta

At first glance, this image may look like a pattern of branching blood vessels. This is actually an image that was taken about 700 km from Earth’s surface of the Mississippi

Delta-- where the water from the Mississippi river flows into the Gulf of Mexico

The underside of a sand dollar shows a branching pattern

Photo of a river in Baja California from space

Antarctic Basket Star

Flow of Energy---High Voltage Dielectric Lichtenberg Figure and Optic Neurons in a Blowfly

Microscopic view of a mycelium which is the part of a fungus (mold) that absorbs nutrients from other living or dead organisms.

This image covers a one-millimeter square

Coral polyps and a snowflake

• Trees are fractal in nature– repeating patterns over and over

False-colour (computer graphics) photograph of a resin cast of the human bronchial tree, the network of airways serving both lungs. The trunk of the tree is the trachea (windpipe, top centre), which branches into the

left and right bronchi. Further divisions occur, with the smallest branches, the bronchioles, terminating in alveoli (air sacs), where gaseous exchange with the blood circulation takes place.

CD in microwave for 5 seconds– don’t do this at home!

Wing veination of a butterfly (left) and fly (right)– insects (especially flies) are identified by their particular wing vein branching – this also suggests evolution– flies have a

common venation scheme--- individuals species are recognized by their slight variation on that scheme

Venation Branching Patters Are Evidence of Evolution

• Fore wing of Lithopanorpa  pusilla • Photograph of (fossil) wing of Lithopanorpa  pusilla

Another example of branching venation patterns as evidence of evolution

• Fore (?) wing of Agetopanorpa  maculata• Photograph of (fossil) wing of Agetopanorpa  maculata