Description
Descriptive measured size ratios only, without inferring prey suitability or feeding recommendations.
Specimen measurements and animal observations depend on a defined body part, reference value, unit, and observation window. A mass fraction, size ratio, or timing share summarizes those inputs. The counting and measurement conventions must stay explicit when comparing specimens or records.
Descriptive measured size ratios only, without inferring prey suitability or feeding recommendations.
When to use this tool
Use Predator Prey Size Ratio Term when you need to compare supplied specimen measurements or observation records under an explicit reference and denominator.
How to use the tool and how it works
- Enter predatorLength, preyLength, predatorMass, preyMass. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read lengthRatio, massRatio, preyMassFraction. Use the output convention below.
Divide predatorLength by preyLength and predatorMass by preyMass for lengthRatio and massRatio. Return preyMassFraction=preyMass/predatorMass, requiring all four quantities positive.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| predatorLength | Predator Length | Required. Finite number; strictly above 0. |
| preyLength | Prey Length | Required. Finite number; strictly above 0. |
| predatorMass | Predator Mass | Required. Finite number; strictly above 0. |
| preyMass | Prey Mass | Required. Finite number; strictly above 0. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| lengthRatio | Length Ratio | Required. Finite number. |
| massRatio | Mass Ratio | Required. Finite number. |
| preyMassFraction | Prey Mass Fraction | Required. Finite number. |
{
"input": {
"predatorLength": 100,
"preyLength": 20,
"predatorMass": 500,
"preyMass": 10
},
"output": {
"lengthRatio": 5,
"massRatio": 50,
"preyMassFraction": 0.02
}
}Limitations and assumptions
- Lengths and masses each need compatible units. These size ratios do not predict predation, feeding suitability, ecological impact, or an animal's health.
- The field tables state structural bounds; the mechanics also specify cross-field constraints. Malformed inputs and unsupported domains cause errors. A successful false flag, empty branch value, or zero placeholder has the meaning stated above and is distinct from an input error.
- Numeric calculations use binary floating point unless exact decimal-integer arithmetic is explicitly stated. No hidden measurement tolerance or decimal rounding is added; nonfinite or out-of-contract results are rejected. Signed zero is exported as zero.
Alternative or Complementary methods
Use compatible measurements and observation records to verify the chosen denominator and reference before interpreting a specimen comparison.
References
Similar or alternative tools
- Animal Track Stride Width Ratio
Return strideWidthRatio=strideLength/trackWidth and relativeStride=strideLength/footLength.
- Body Condition Size Reference Residual
Observed versus externally predicted mass residual on an explicit arithmetic or log scale.