Natal Homing
Definition
The behavior by which female sea turtles return to the beach where they hatched to lay their own eggs. This produces strong genetic structuring between nesting populations, making mitochondrial haplotypes useful for geographic assignment.
- Behaviour
- Female sea turtles return to their hatching beach to nest
- Genetic effect
- Strong population structuring between nesting sites
- Forensic marker
- Mitochondrial haplotypes
- Application
- Geographic assignment of seized or found turtles/products
Common questions
Why is mitochondrial DNA specifically useful for natal homing analysis rather than nuclear DNA?+
Mitochondrial DNA is maternally inherited without recombination, so it directly tracks the maternal lineage tied to a particular nesting beach through natal homing, producing distinct haplotype frequencies between rookeries that nuclear DNA, which mixes from both parents and disperses via male-mediated gene flow, does not preserve as clearly.
How does natal homing let investigators trace the origin of a seized turtle or turtle product?+
By comparing the mitochondrial haplotype of a sample against a reference database of known nesting-population haplotype frequencies, investigators can statistically assign the likely rookery of origin, which helps identify which protected population is being illegally exploited even though it cannot pinpoint an individual beach with certainty.
Does natal homing mean male sea turtles never disperse between nesting populations?+
Natal homing behavior is primarily documented and strongest in nesting females; males are understood to disperse more widely between foraging and breeding areas, which is one reason nuclear genetic markers show less population structure than the maternally inherited mitochondrial markers do.
Related terms
- Hawksbill (Eretmochelys Imbricata)
- The sea turtle species that produces tortoiseshell. Distinguishable by its narrow pointed beak, overlapping (imbricate) scutes, and four pairs of lateral scutes....
- Imbricate vs Juxtaposed Scutes
- Hawksbill scutes overlap like roof tiles (imbricate); green and most other sea turtle scutes meet edge-to-edge without overlapping (juxtaposed). This difference is...
- Mitochondrial Haplotype
- A specific variant of mitochondrial DNA sequence. Because mitochondria are inherited maternally, haplotypes track female lineages and cluster by nesting rookery in...
- PIT Tag
- Passive integrated transponder: a small RFID chip implanted under the skin of tagged sea turtles. Can be scanned from a carcass even...
- Scute
- An individual plate of keratinous shell that overlaps with its neighbors on the outer carapace of a sea turtle. Count, arrangement, and...