AnAge entry for Ursus arctos

Classification (HAGRID: 02703)

Taxonomy
Kingdom: Animalia
    Phylum: Chordata
        Class: Mammalia (Taxon entry)
            Order: Carnivora
                Family: Ursidae
                    Genus: Ursus
Species
Ursus arctos
Common name
Brown bear and grizzly bear

Lifespan, ageing, and relevant traits

Maximum longevity
40 years (captivity)
Source
ref. 671
Sample size
Large
Data quality
Acceptable
Observations

The implantation of the fertilized eggs is usually delayed for about 4 months. It has been suggested that these animals may live up to 50 years [0434], which is doubtful. These are common animals in zoos, and so far record longevity in captivity is about 40 years for one wild born female [0671]. An aged specimen had neurofibrillary tangles [0955].

Life history traits (averages)

Female sexual maturity
1,313 days
Male sexual maturity
1,313 days
Gestation
103 days
Weaning
213 days
Litter size
2 (viviparous)
Litters per year
0.4
Inter-litter interval
852 days
Weight at birth
510 g
Weight at weaning
26,000 g
Adult weight
277,500 g
Postnatal growth rate
Maximum longevity residual
120%

Metabolism

Typical body temperature
310ºK or 37.3ºC or 99.1ºF
Basal metabolic rate
Not yet available

References

External Resources

Integrated Taxonomic Information System
ITIS 180543
Animal Diversity Web
ADW account
Encyclopaedia of Life
Search EOL
NCBI Taxonomy
Taxonomy ID 9644
Entrez
Search all databases
Ageing Literature
Search Google Scholar or Search PubMed or Search Scirus
Images
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Internet
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