recent advances in molecular genetics introduce questions

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• The Species Concept in Conservation
• The species concept of conservation has been
  questioned because
• recent advances in molecular genetics introduce
  questions. Are wolves in Algonquin Park gray
  wolves (historical view) or red wolves (recent
  evidence based on DNA analyses)? If the latter,
  are we going to protect one or both species?
• Population biologists question whether the
  species is the appropriate conservation unit.

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3. Some argue that species-based conservation
efforts may be misplaced since they are
biased in favour of mammals and birds at the
expense of other microscopic or unattractive
taxa and that the basis should be ecosystem
oriented. 4. Still others suggest conservation of
'endangered phenomena', such as that of
migrating populations of monarch butterflies,
is necessary.
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• In the U.S., these various views came to a head
  in the debate about protection for the Florida
  panther. The arguments came down to
• Protection of the ecosystem, not the species.
  Conservation groups were split down the middle,
  with one group suing the US government to stop a
  captive breeding program intended to protect the
  species. They argued that protecting the species
  and not its habitat was foolish and ineffective.
  The other side wanted to initiate captive
  breeding to build the population. The resolution
  will be presented later as a case study. Both
  sides, however, did want to protect panthers.

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2. Is the Florida panther worthy of protection?
Developers argued that the species should be
removed from the endangered species list since it
was a mongrel population. A female puma (panther)
originally from Chile was released in the
Everglades during the 1950's after they no longer
wanted her at a zoo in New York City.  She bred
successfully and, because of her distinctive
genotypic composition, her genes can be
tracked in many of the Florida panthers found
today.  Since it was then a hybrid species, by
the Endangered Species Act criteria at that time,
the species should not have been protected.
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• Counter arguments for protection included
• subspecies, like the Florida panther, are the
• genetic stock from which new species are
  derived
• and thus they deserve protection
• b) subspecies are locally-adapted organisms that
  may
• be distinctive from other subspecies
• c) the extremely small existing populations of
  panthers has resulted in significant inbreeding
  depression. Thus, rather than lamenting
  introduction of new alleles into the population
  that this Chilean puma brought to the
  Florida panther, it should be applauded for
  expanding the gene pool.

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Largely because of this case, ESA guidelines
regarding interbreeding were subsequently
withdrawn and not replaced. Canadas Species at
Risk Act (SARA) was given royal assent on
December 12, 2002, and was implemented in 2003.
Its focus is species-based, with the view that
endangered species can be protected only through
protection of their habitat. Problem protection
for endangered species is legislated on federally
owned and managed lands. Many provinces have
joined in this protection on crown lands they own
or manage. Protection does not extend into
private land holdings.
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Canada has also recognized vulnerability of
specific sub-species or populations (e.g. St.
Lawrence population of Beluga whales).
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• Biological Species Concepts
• Historic or Typological View - species viewed as
  having fixed characters variation is considered
  unimportant, unfortunate and unusual. Type
  specimens define the characteristics.
• Population or Evolutionary View - rather than
  focus on the norm, this view considers variation
  the spice of life. Variation is intrinsic to
  species and is important since it is the raw
  material through which natural selection and
  evolution (speciation) occur. This view accepts
  geographic variation as important in adaptation
  and speciation.

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• Biological Species a definition
• A species is a group of actually or potentially
  interbreeding organisms separated from other such
  groups.
• Problems
• what if species (really populations) are not
  sympatric and therefore never have chance to test
  species determination?
• 2) what about asexual species?
• 3) what about chronospecies (species change
  through
• time, as in sequences in the fossil record)?
• 4) what about species like bacteria that undergo
• conjugation or introgression (plants)?

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• An alternative view is the Phylogenetic Species
  Concept (PSC) - Classification is based on
  branching relationships among taxa with respect
  to shared derived characters rather than on
  reproduction.
• A species is the smallest cluster of organisms
• sharing common features with recognizable
  parental
• stock
• - This scheme would recognize subspecies as
• species thus this scheme recognizes many more
• species than those classically accepted. In
  some
• cases, species delineations are made primarily
  on
• the basis of variation in DNA sequences or
• allozymes.

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A cladogram for the chordates