At the end of the 19th century,
The French biologist Alexandre Yersin discovered the germ Yersina pestis.
Yersina pestis spread the "Black Death". With the help of modern
microbiologist's study with a namatode (C. elegans), genes that may play a part
in the transmission of plague have been identified. Along with this knowledge,
the microbiologists understood that the bacillus travelled from person to
person through the air and from bites from infected fleas and rats. According
to biologist Paul-Louis Simond, the bacteria blocks the digestive tracts of the
fleas and stimulates them to bite and people repeatedly, injecting and
spreading the bacteria. The bacteria hitchhike in immune cells in lymph nodes
and the infection begins and transmits to others. Antibiotics are then chosen to fight the bacteria.
It is possible to find snow covered mountains in India along the equator because "<span>c. As elevation increases, temperature decreases". This seems counter intuitive, but the surface of the planet is much hotter because it absorbs heat </span>
Answer:
The fish did not yet exist when the old layers of rocks were deposited. In fact, animals with hard parts did not evolve until about 600 million years ago, which is only about 13% of the 4.5 billion year age of the Earth. Multicellular animals without hard parts left tracks in older sediments, but had no fossilize-able body parts.
Explanation:
