Homeostasis threatens these tissues
DNA basically contains your genes. Basically, everything about you is from your DNA.
The atomic number is the number of protons per atom. In a neutral atom, the number of electrons equals the number of protons. The periodic table represents neutral atoms. ... The atomic mass number is equal to the number of protons plus neutrons, which provides the average weight of all isotopes of any given element. Isotopes are atoms of the same element that have different masses. Atoms have a mass that is based largely on the number of protons and neutrons in their nucleus. Electrons are organized into shells and subshells about the nucleus of an atom. The chemical elements are arranged in a chart called the periodic table.
Answer:
According to National Geographic, ostriches are a part of a very small group of birds that cannot fly because unlike most birds, their small wings are not strong enough to carry their body for flight and their breastbone isn't balanced enough for flying. Birds that are unable to fly are called ratites.
A number of scientists namely Thomas Huxley, Richard Owen, and others have tried to show that these ratites are actually related to each other and eventually, it was discovered that they all had one thing in common, the way the bones at the roof of the mouth were arranged was similar to that of reptiles rather than other birds.
Richard Owen found and assembled the remains of an extinct ostrich skeleton which was an extinct moa and contrary to already held opinion, one ratite known as tinamous did not really fit with the profile of a ratite because it could fly, even though almost grudgingly and they possessed keeled sternum which suggests that they evolved from flying birds.
DNA tests showed that tinamous evolved within ratites and not necessarily as a separate entity. The tests also showed that moas and tinamous are related.
It was also speculated that the division of the supercontinent Pangaea southern side led to the separation of flightless ratite ancestors, causing each landlocked group to evolve and become the flightless birds we know today such as the ostrich, rheas, etc.
