Biomechanics of Trees

Trees are shaped by their surrounding and the growing environment. Every region has a bunch of endemic and native tree species. Every native tree has a particular tree form and different wood physical and biomechanical properties. Arboreal habitats pose diverse mechanical challenges for animal locomotion through trees, such as branch incline, dealing with obstructions, balancing, etc. Animals residing in these trees adapt to these changes and overcome the challenges.

Balancing

Moving in a tree requires many balancing techniques to save oneself from tipping over and falling. 

• The arboreal animals face the issue of a narrow base of support in a horizontal branch and tipping to the side due to imbalance. 
• The vertical and steep branches do not pose the threat of tipping over but slipping downwards or pitching backward creates a difficult obstruction to the movement of limbed animals. 
• Branches with wider diameters require much more balance than thinner branches as the animal cannot place their forelimbs closer to the center of the branch, which might lead to a slipping downward scenario. 

Branch Diameter

Many terrestrial animals deal with the center of mass swinging from side to side during movement on the land surface. 

• But in arboreal locomotion, the center of mass tends to edge over the branch diameter, increasing the risk of toppling over and falling. 
• Not only do animals deal with varying branch diameters while moving, but they also rely on food consumption on the branches, depending on their ability to adapt various grasping techniques to clamp themselves for balance. 

Branch Inclination

Animals have to deal with the branches placed at an angle to gravity. 

• Being vertically oriented poses a special problem in the arboreal habitat, making it more difficult to deal with gravity moving up and down the branch while avoiding the chance of falling. 
• As the branch inclination goes up, animals have to fight the force of gravity with the ability to raise their body. To overcome this challenge, arboreal species engage all their limbs, emphasizing upper body strength and increasing the frequency of their movement pattern sequence. 
• Another issue of vertically inclined branches is the descendant movement. They must fight the change in gravity to control their gait while moving down and declining the risk of falling. 
• To achieve this, arboreal animals increase their limb contact with the branch, increasing frictional force and braking power.

Dealing with Obstructions

Obstructions lead to impeding locomotion for limbed animals. These obstructions can be the branches of the tree the animal is in or branches from neighboring trees. This poses a challenge for limbed animals as it decreases the frequency of movements. But these obstructive branches are the additional contact point for better directional locomotion for crawling animals like snakes.