More Harmful Effects of Smoking Weed While Breastfeeding. More medical studies need to be done to determine marijuanaâs effects on breast milk, but below are some of the areas studies have indicated contain risk factors.urthermore, marijuana use can diminish the abilities of a mother to take care of her newborn. The American Academy of Pediatrics advises nursing mothers not to use marijuana while breastfeeding. However, in some states medical marijuana is used to treat anxiety and other medical conditions.
We can see fossils of many other reptiles in rock of the same age and even older, but Archaeopteryx lithographica is the oldest known fossil to have feathers. We conclude that this animal is a link between reptiles and birds and that birds are descended from reptiles.ossils can be used to recognize rocks of the same or different ages. The fossils in this figure are the remains of microscopic algae. The pictures shown were made with a scanning electron microscope and have been magnified about 250 times.
Stratigraphy is the science of deciphering the layer-cake that is the sedimentary record. Rocks normally form relatively horizontal layers, with each layer younger than the one underneath it. If a fossil is found between two layers whose ages are known, the fossil's age is claimed to lie between the two known ages.he fossils themselves are referred to as the fossil record. The fossil record was one of the early sources of data underlying the study of evolution and continues to be relevant to the history of life on Earth.