Why are raptors a indicator species?

Indicator species may provide useful substitute for large scale surveys to monitor biodiversity. Weconducted surveys in the Afro-alpine habitats of the Bale Mountains National Park (BMNP) with theobjective of identifying indicators for the species richness of the raptor guild. Raptors were countedby scan sampling technique from a suitable vintage point. Three classes of 18 sample units groupedaccording to the variability of the moorland ecosystem in the magnitude of process variables importantfor raptor species richness were used in determining the indicator value of species as a function of their abundance concentration and the percentage of species occurrence per sample group. Thisprocedure determined indicator values for all species in the resident raptor community. Comparisonwith randomly expected values demonstrated that only Aquila verreauxiiand A. chrysaetoshaveindicator values that were significantly larger than the randomly expected values. The species richnessestimated using the abundances of these two species predicted the observed species richness of thewhole community in a linear regression model that explained 66% of the deviance in the data set.Furthermore, the species richness of the community predicted by process variables had correlation of very high significance with that predicted by the indicator species. We have thus identified twoindicator species to a raptor guild of the BMNP and demonstrated that these two species encapsulatedmost of the information regarding the species richness response of the guild to key process variablesin the Afro-alpine moorland ecosystem. Our findings contribute significantly to current and futureefforts of monitoring the biodiversity of the park providing a cheap and quick means of data generationrelevant for making management decisions.                               Hope this helped! :)

answer: carbon 14 can only be used to determine the age of the organisms that were once living, and igneous rocks are non living.

explanation:

carbon 14 dating is used to determine the age of the sample by estimating the amount of carbon 14 present in the sample and then comparing it with a reference standard.carbon 14 is a isotope of carbon which is radioactive and unstable. carbon 14 is assimilated by all plants and animals throughout their life from carbon dioxide. however, one the organisms die they stop this assimilation and the carbon 14 content starts to decrease.by knowing how much of carbon 14 is left in an organism after his death, one can estimate the age of the organism. the materials whose age can be estimated by carbon 14 method are the organic compounds. however, some inorganic compounds such as aragonite   shell can also be dated.however, if we consider the igneous rocks it is a non living component which never accumulated carbon 14 in it and thus, we cannot use carbon 14 dating method to estimate its age.

Atissue is a group of connected cells that have a similar function within an organism.