For people who do not believe in macroevolution, try to refute
the below example of atavism
http://dictionary.reference.com/search?q=atavism
atavism
The reappearance of a characteristic in an organism after several
generations of absence, usually caused by the chance recombination
of genes.
http://www.talkorigins.org/faqs/comdesc/section2.html#atavisms_ex1
Many famous examples of atavisms
exist, including (1) rare formation of extra toes (2nd and 4th
digits) in horses, similar to what is seen in the archaic horses
Mesohippus and Merychippus, (2) atavistic thigh muscles in
Passeriform birds and sparrows, (3) hyoid muscles in dogs, (4)
wings in earwigs (normally wingless), (5) atavistic fibulae in
birds (the fibulae are normally extremely reduced), (6) extra toes
in guinea pigs and salamanders, (6) the atavistic dew claw in many
dog breeds, and (7) various atavisms in humans (one described in
detail below) (Hall 1984).
Probably the most well known case of atavism is found in the
whales. According to the standard phylogenetic tree, whales are
known to be the descendants of terrestrial mammals that had
hindlimbs. Thus, we expect the possibility that rare mutant whales
might occasionally develop atavistic hindlimbs. In fact, there are
many cases where whales have been found with rudimentary atavistic
hindlimbs in the wild (see Figure 2.2.1; for reviews see Berzin
1972, pp. 65-67 and Hall 1984, pp. 90-93). Hindlimbs have been
found in baleen whales (Sleptsov 1939), humpback whales (Andrews
1921) and in many specimens of sperm whales (Abel 1908; Berzin
1972, p. 66; Nemoto 1963; Ogawa and Kamiya 1957; Zembskii and
Berzin 1961). Most of these examples are of whales with femurs,
tibia, and fibulae; however, some even include feet with complete
digits.
For example, Figure 2.2.1 shows the bones from the atavistic legs
of a humpback whale. These bones are the remnants of one of two
symmetrical hind-limbs found protruding from the ventral side of a
female humpback whale, captured by a whaling ship from the Kyuquot
Station near the west coast of Vancouver Island, British Columbia,
in July 1919. Two officials of the Consolidated Whaling Company
were understandably impressed by this discovery, and they removed
one of the legs and presented the skeletal remains to the
Provincial Museum in Victoria, B.C. (The other leg was evidently
taken as a "souvenir" by crew members of the whaling ship). The
museum's director, Francis Kermode, presented the bones to Roy
Chapman Andrews from the American Museum of Natural History (AMNH)
in New York. Andrews reported the findings, along with photographs
of the whale from the whaling crew, in American Museum Novitates,
the journal of the AMNH. Andrews identified in the remains a
shrunken cartiliginous femur, tibia, tarsus, and metatarsal. Both
legs initially were over four feet long and covered in normal
blubber and skin. For comparison, an average adult female humpback
is around 45 feet long. The femur, composed of unossified
cartilage, had shrunken from 15 inches to 4.5 inches. When attached
to the whale, the femur was completely inside the body cavity and
attached to the pelvic rudiments (humpback whales have vestiges of
a pelvis inside the abdominal wall). This extraordinary finding is
unlikely to be repeated, as the International Whaling Commission
gave humpback whales worldwide protection status in 1966, after
sixty years of uncontrolled human predation had decimated the
population.
In short, whales with legs have been found and
documented. It is believed in the scientific comunity tat tis
occurs because sometime in the whale evolution it is a creature
with legs but had evolved back into wat it is now. Otherwise please
explain a reason for tis phenomenon
