# Variable: costOfTransport

[**lifecycle-kit**](https://jonbogaty.com/lifecycle-kit/api/readme/index.md)

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[lifecycle-kit](https://jonbogaty.com/lifecycle-kit/api/readme/index.md) / [bio-laws](https://jonbogaty.com/lifecycle-kit/api/bio-laws/readme/index.md) / costOfTransport


# Variable: costOfTransport {#variable-costoftransport}


> `const` **costOfTransport**: `object`

Defined in: [bio-laws/lifeHistory.ts:188](https://github.com/jbcom/lifecycle-kit/blob/074e4e7b8038d3e2de9eb44c4b5b5aee0ef02b48/src/bio-laws/lifeHistory.ts#L188)

Cost of transport — energy per unit distance per unit mass, J/(kg·m).

Source: Schmidt-Nielsen, K. (1972). "Locomotion: Energy Cost of Swimming,
Flying, and Running." Science, 177(4045), 222-228.

Validated across 27 orders of magnitude of body mass, which makes it one of
the most robust relationships in the whole of biomechanics. Swimming is
cheapest because buoyancy carries the weight; burrowing is brutal because
the animal has to move the ground as well as itself.

This is what makes a room's activity genuinely cost something different.


## Type Declaration {#type-declaration}



### burrowing {#burrowing}


> `readonly` **burrowing**: (`massKg`) => `number`


#### Parameters {#parameters}



##### massKg {#masskg}


`number`


#### Returns {#returns}


`number`


### flying {#flying}


> `readonly` **flying**: (`massKg`) => `number`


#### Parameters {#parameters-1}



##### massKg {#masskg-1}


`number`


#### Returns {#returns-1}


`number`


### running {#running}


> `readonly` **running**: (`massKg`) => `number`


#### Parameters {#parameters-2}



##### massKg {#masskg-2}


`number`


#### Returns {#returns-2}


`number`


### swimming {#swimming}


> `readonly` **swimming**: (`massKg`) => `number`


#### Parameters {#parameters-3}



##### massKg {#masskg-3}


`number`


#### Returns {#returns-3}


`number`