Age and growth of Palaeoloxodon huaihoensis from Penghu Channel, Taiwan: significance of their age distribution based on fossils

PeerJ

article

Jia-Cih Kang¹  Chien-Hsiang Lin¹  Chun-Hsiang Chang¹ 

[1] Department of Life Science, Tunghai University;Biodiversity Research Center;Department of Geology, National Museum of Nature Science

关键词: Age distribution;    Pleistocene;    Subtropical West Pacific;    Elephant age group;    Lamellar frequency;    Tooth morphology;    Taiwan;    Penghu Channel;   

DOI  :  10.7717/peerj.11236

学科分类：社会科学、人文和艺术（综合）

来源: Inra

【 摘 要 】

Dental material attributed to Palaeoloxodon huaihoensis from the Middle to Late Pleistocene were recovered over decades from the Penghu Channel during commercial fisheries activities. The National Museum of Nature Science (NMNS) has a collection of such dental material, which differs in size and morphology and likely represents ontogenetic variation and growth trajectory of various age groups of P. huaihoensis. However, little is known regarding age determination. By using length of dental material, enamel thickness (ET), and plate counts, we established the method to distinguish the age of the species, which is directly derived from the extant African forest elephant Loxodonta africana. When measuring signs of allometric growth, we found that in both the upper and lower jaws, tooth width was correlated negatively with lamellar frequency but positively with ET. In the same age group, the number of lamellae was higher in P. huaihoensis than in L. africana. The reconstructed age distribution indicated no difference in the upper or lower jaw. Notably, within our sample, P. huaihoensis is skewed towards adult and older individuals with median age between 33–34.5 years and differed significantly from that of Mammuthus primigenius in the European Kraków Spadzista site. This age distribution pattern is speculated to be related to the harsh environmental conditions and intense intraspecific competition among P. huaihoensis during the last ice age.

【 授权许可】

CC BY