There have been several hundred pits found on the lunar surface. These lunar pits are hypothesized to be remnant lava tubes. Considering the Moon is not geologically active, these lava tubes could be an excellent shelter. Not only could these lava tubes be a shelter for human habitat, but they could also be an ideal location to shelter seeds, sperms, eggs, and DNA of endangered animal and plant species of Earth in a modern Ark. Lunar lava tubes are excellent locations that are sheltered from radiation, temperature swings, and small meteorite impact. Earth is undergoing significant changes resulting in loss of whole ecosystems, extinction of many thousands of species, and endangering a critical food chain that could threaten human survival. Earth faces dire threats of nuclear war, accelerated climate change, environmental poisoning, and natural disasters such as super-volcanic eruptions, earthquakes, tsunamis, and asteroid impact. These lunar pits are nearly 80 m deep and 80-100 m in diameter. The temperature is expected to be a balmy - 25 °C compared to surface temperatures reaching 130 °C during the daytime and up to -150 °C in the night-time. To store seeds, sperms, eggs, and DNA would require cryogenic temperatures below -180 °C. It is possible to store grains, eggs, sperms safely, and DNA at these cryogenic temperatures without risk of decomposition over many decades, if not centuries. This paper extends our earlier concept of building a human base inside a lava tube network to develop a modern-day robotic Ark containing seeds, eggs, sperms, and DNA. Here we present a modular, expandable design of a modern-day Ark that will preserve bio-material. The Ark will be powered using photovoltaics located on the lunar surface. Power will be generated during the lunar day sufficient to keep the Ark refrigerated both during the lunar day and night. These biomaterials will be stored in cassette storage units packaged into rotating shelves. In turn, the shelves will be placed in a modular cylindrical storage room that is 25 m in length and have a diameter of 10 m. Access to these cylindrical storage rooms will be possible using vertical shafts containing elevators constructed into the lunar pits. The vertical shafts will also include laboratories to verify the stored bio-material integrity and prepare for transport back to Earth. A series of mobile robots equipped with 7-DOF robot arms will be used to retrieve and deposit a cassette containing the cryo-preserved biomaterial. In this paper, we analyze the concept's principal feasibility, examining the Ark's structures, thermal design, and power needs.