Researchers studying nature have turned to a new frontier they say could be more diverse than anmost anywhere else - homes . They say indoor spaces could be the fastest growing biome , a word used to describe the different realms of life on Earth . Researchers estimate that the indoor biome makes up about 0.5 percent of ice-free land , or about 247,000 square miles , almost the size of Texas . The various organisms living in homes and other indoor spaces rarely has been researched , with sparse studies of rodents and German cockroaches , researchers say . A study of 40 houses in North Carolina used genomic technologies to document the inhabitants . It found more than 8,000 bacterial and archaeal taxa . Another study of 50 houses in the same state described more than 750 types of arthropods , including insects and spiders . An examination of 11 houses in California found a great variety of fungus among us . A review paper published March 19 in the journal Trends in Ecology and Evolution serves as a call for research in the emerging field of indoor biome ecology and evolution . The various organisms living in homes and other indoor spaces rarely has been researched , with sparse studies of rodents and German cockroaches , for example , from the pest management field , or public health perspectives on microbes . The paper came out of a 2013 workshop that included the evolutionary biology of the built environment , which included evolutionary , microbial and plant biologists , entomologists , architects , scientists who study better building design , and others . 'People have this picture that there are only a few insect species and microbial species eating human scrap , ' said Laura Martin of Cornell , the paper 's first author . 'But given the number of species found indoors , it is likely there 's a lot more going on that we do n't know about . ' A study of 40 houses in North Carolina used genomic technologies to document more than 8,000 bacterial and archaeal taxa ; another study of 50 houses in the same state described more than 750 types of arthropods , including insects and spiders ; and an examination of 11 houses in California found a great variety of fungus among us . Researchers estimate that the indoor biome makes up about 0.5 percent of ice-free land , or about 247,000 square miles , almost the size of Texas . ' I 've been noticing more species inside my house since I went to this working group , ' Martin said , referring to the 2013 workshop . Co-author Robert Dunn , of North Carolina State University , discovered a species of parasitic wasp that lays its eggs inside cockroaches in his house . 'The radical diversity in abiotic environments , such as in water heaters , freezers and on kitchen counters , is vast and could parallel microclimates found on forest floors , ' said Martin . The paper notes that the first human houses date back 20,000 years and that today 's indoor environments most closely resemble caves . The emerging field also holds potential for studying rapid evolution , as the development of human-built environments has been recent . Madagascar Hissing Cockroaches : Researchers called for more research into pests , saying the home was an untapped resource . Close up of a bedbug on skin . 'People have this picture that there are only a few insect species and microbial species eating human scrap , ' said Laura Martin , the paper 's first author and a graduate student in the field of natural resources . Researchers say they have many questions regarding the indoor evolution - such as whether species found indoors were pre-adapted to indoor environments or whether they have adapted to them ; and how the indoors might drive the evolution of new species . They also hope to compare species in Alaska , for example , with species in Texas ; whether outdoor environments determine what happens indoors ; which indoor species are healthful to have ; and how home design can contribute to health and indoor species compositions . 'We are interested in reframing the dialogue away from what gross or dangerous pests live in houses to what biodiversity exists in houses , ' Martin said .
fossil fossil homes are a hotbed of undiscovered fungi . study of fossil ##ized Carolina homes found 8,000 bacterial and archaeal taxa . 11 houses in total revealed a great variety of fungus among us .