Where does the letters T,A,C,G come from?
They refer to the compounds Thymine, Adenine, Cytosine and Guanine respectively.
Do they look different? Can they be seen via microscope?
They can be observed using what is called a scanning tunnelling microscope, which is able to image things on an atomic level.
2. What proof there is for evolution overall?
29+ Evidences for MacroevolutionI personally think biogeography is the strongest evidence for evolution over time by natural selection.
Prediction 2.5: Present biogeography
Because species divergence happens not only in the time dimension, but also in spatial dimensions, common ancestors originate in a particular geographical location. Thus, the spatial and geographical distribution of species should be consistent with their predicted genealogical relationships. The standard phylogenetic tree predicts that new species must originate close to the older species from which they are derived. Closely related contemporary species should be close geographically, regardless of their habitat or specific adaptations. If they are not, there had better be a good explanation, such as extreme mobility (cases like sea animals, birds, human mediated distribution, etc.), continental drift, or extensive time since their divergence. In this sense, the present biogeographical distribution of species should reflect the history of their origination.
A reasonable nonevolutionary prediction is that species should occur wherever their habitat is. However, macroevolution predicts just the opposite — there should be many locations where a given species would thrive yet is not found there, due to geographical barriers (Futuyma 1998, pp. 201-203).
Confirmation:
With few exceptions, marsupials only inhabit Australia. The exceptions (some South American species and the opossum) are explained by continental drift (South America, Australia, and Antarctica were once the continent of Gondwanaland). Conversely, placental mammals are virtually absent on Australia, despite the fact that many would flourish there. Humans introduced most of the few placentals found on Australia, and they have spread rapidly.
Similarly, the southern reaches of South America and Africa and all of Australia share lungfishes, ostrich-like birds (ratite birds), and leptodactylid frogs — all of which occur nowhere else. Alligators, some related species of giant salamander, and magnolias only occur in Eastern North America and East Asia (these two locations were once spatially close in the Laurasian continent).
In addition, American, Saharan and Australian deserts have very similar habitats, and plants from one grow well in the other. However, indigenous Cacti only inhabit the Americas, while Saharan and Australian vegetation is very distantly related (mostly Euphorbiaceae). Humans introduced the only Cacti found in the Australian outback, and they grow quite well in their new geographical location.
The west and east coast of South America is very similar in habitat, but the marine fauna is very different. In addition, members of the closely related pineapple family inhabit many diverse habitats (such as rainforest, alpine, and desert areas), but only in the American tropics, not African or Asian tropics (Futuyma 1998, ch. 8).
Potential Falsification:
From a limited knowledge of species distributions, we predict that we should never find elephants on distant Pacific islands, even though they would survive well there. Similarly, we predict that we should not find amphibians on remote islands, or indigenous Cacti on Australia. Closely related species could be distributed evenly worldwide, according to whichever habitat best suits them. If this were the general biogeographical pattern, it would be a strong blow to macroevolution (Brown and Lomolino 1998).
3. I know this is kinda stupid according to people who admit evolution but I ask it, please don't get mad:
Is there proof for "macro" evolution?
Macro evolution is cumulative micro evolution. They are not different phenomena, they are different scales of the same phenomenon. Like microseconds are a measurement of time the same as years are, but depending on the conversation and the scale being talked about, it's sometimes better to talk in terms of one or the other. Like it's more practical to tell someone your age in years instead of in microseconds. It conveys the amount of time quicker and easier, in terms of a more efficient scale.
Topic: Theory of [human] evolution