0000000000666971
AUTHOR
Oleg A. Lebedev
Palaeozoogeographical connections of the Devonian vertebrate communities of the Baltica Province. Part II. Late Devonian
Abstract Late Devonian vertebrate communities within the Baltica zoogeographical Province are analysed for intra- and interprovincial connections. Components within the category of provincial endemics are used to assign the communities to a particular zoogeographical province. Marine and continental, presumably freshwater types of vertebrate dispersal are outlined. During the Late Devonian marine dispersal is displayed by ptyctodonts, struniiforms, and some dipnoans, and continental dispersal by psammosteids, acanthodians, and some arthrodires. Isolation of communities is reflected by predominance of local and provincial endemics; the majority of polydemics and cosmopolitans records wider c…
Bite marks as evidence of predation in early vertebrates
Study of lifetime bite traces on agnathans and fish (or gnathostomes) from Ukraine, Estonia, Latvia and north-western and central European Russia reveals evidence of predator–prey relationships in communities of Devonian age. Numerous bite traces on skeletal parts of agnathan pteraspidiforms and psammosteiforms, placoderm arthrodires and antiarchs and sarcopterygian porolepiforms and osteolepiforms are described. Evidence of healing shows that prey organisms responded to predation by reconstruction of damaged skeletal elements. Ichthyofaunistic analysis is used to establish possible predators. The most probable predators in the Middle and Late Devonian communities are sarcopterygian porolep…