Scientific advances in the study of evolutionary developmental biology (evo-devo) have demonstrated that another factor has had as much of an impact as specific alterations in the genes on the macroevolutionary changes in body plans that have been observed through time. This factor is .

The phenomena of (evo-devo) is the part of biology related to how variations in embryonic growth throughout single peers are related to evolutionary changes that occur between generations.One of the scientist who worked on this phenomena named  charles darwin argued for the importance of growth (embryology) in understanding evolution. Nevertheless, afterward the detection in 1900 of Mendel's research on genetics, any relationship between development and evolution was not considered important for understanding evolutionary processes or as a black box that was difficult to see. Research in the past two decades has opened that black box, revealing how evo-devo studies highlight the mechanisms that link genes (the genotype) to structures (the phenotype). This is vitally important because genes do not form structures. Development processes create structures using gene-provided road maps, but they also use many other signals - physical forces such as mechanical stimulation, ambient temperature, and interaction with chemicals produced by other species - often species in completely different kingdoms. As in communications amongst microorganisms and squid or between leaves and larvae. Genes not only do not form structures (the phenotype), but new properties and mechanisms emerge during embryonic development: genes are differentially regulated in different cells and locations; Similar cell aggregations provide the cellular resources (modules) from which tissues and organs arise; modules and differentiated cell populations interact to establish development along particular tracks; and organisms interact with their environment and create their niche in that environment. Such interactions are often called "epigenetic," meaning that they direct gene activity using mechanisms that are not encoded in the DNA of the genes. This article reviews the origins of evo - devo, how the field has changed in the last 30 years, assesses the recognition of the importance for the development and evolution of mechanisms that are not encoded in DNA, and assesses what the future holds. could bring for evo– devo. Though difficult to know, past communicates us that we could expect more of the same; expansion of evo - devo in other areas of biology (ecology, physiology, behavior); absorption of evo-devo by evolution or a unification of biology in which evo-devo plays an important role.

americans began to notice growing differences between the northern and southern sections of the country. there were more people living in cities in the north, which made it more urban. more people lived on farms in the south, which made it more rural. while many people were farmers in the northern states, there were now other ways to make a living, such as working in mechanical cotton gins factories manufacturing cloth, tools and other goods. people in the north supported high tariffs on goods imported from europe because the extra cost encouraged people to “buy american” instead. in the southern states, planters did not like tariffs because they sold most of their production to europe and bought their tools from there as well. southerners believed the protective tariff was something that only northern factory owners keep their profits high. so the southern politicians came up with an idea. they would opt out. they would simply ignore the protective tariff. it was ‘null and void’ in south carolina. the state would not collect the taxes on goods imported into south carolina, no matter what the president said they had to do. this decision led to the nullification crisis.

answer: that would be cheating

explanation: