Answer:
millipedes were the first of these animal groups to evolve.
Explanation:
Fossils are structural remains of animals from the past. As these animals die, it takes years for the remains to be buried.
The millipedes are at the lower layer of the rock, next to insects, amphibians, and then rodents. This shows that millipedes existed and evolved before the rest of the found animal fossils.
Answer:
reduced hybrid fertility
Explanation
The formation of mules from the cross between female horses (mares) and male donkeys (jacks) is an example of reduced fertility because the mules are sterile and they cannot give birth to babies.
Reason:
Because mule cannot produce sperms. This has to do with his genetics. A mule has 63 chromosomes in total. He gets 32 chromosomes from his mom (that is a horse) and 31 chromosomes from his Dad (that is a donkey). As we know, it is very important for reproduction that chromosomes hould be present in two sets with equal numbers.
To reproduce he needs equal number of chromosomes because we know during meiosis chromosomes segregate and half number goes in daughter cells. But in case of mules he has an extra chromosome due to which he cannot undergo correct meiosis and produce sperms. That is ahy he stays sterile throughout his life. This is called reduced hybrid fertility
Hope it helps!
The air that we breathe is mostly made up of nitrogen (78%). 21% is oxygen which is needed for animals and humans in respiration and 0.03% is carbon dioxide which is needed for plants to make energy in a process called photosynthesis. The bit that is left is made up of rare gases like helium and argon and methane.
