Species Concept What is a species? A simple question has troubled biologist for more then two centuries An agreement is still lacking Species concepts are heterogeneous both in theory and practice but……… a rose is a rose is a rose

but……… a rose is a rose is a rose

Rose harvesting

The ambiguity of the species category Biological world is a continuum of organization ………..what exactly is an “individual” in shrubs, in a planarian worm?

The ambiguity of the species category Biological species is a population whose members have potential to interbreed and produce fertile offspring …………it applies only to bisexual organisms, excluding asexual ones, and overemphasizes between-population reproductive system……..

Process and Pattern Concepts Process of segregation, isolation and recognition responsible for the differentiation of population Pattern: comparison of the product of those differentiation process

Typological species concepts, based on “essential” features Carl von Linne` Evolutionary theory: Darwinism Polytypic species: geographical variations, varieties, subspecies, trinomens, differed only in detailed coloration or other superficial characters

Why define a species? Declining species populations increasingly vulnerable to extinction Did we lose a “species” , when we make a mistake in defining subspecies and species? Is it the best interest for species conservation to introduce individuals from remote population into threatened local population?

The definition of a species is also critical as legal issue, as it relates to efforts to preserve habitat to save threatened endangered species At the end: morphological species is a classical still alive, useful and necessary before a new one system with robust and accepted species concept