These two abbreviations both mark time before Year 1 on a historical timeline.
BC and BCE
Historians use this Latin term—abbreviated as c. or ca.—when they do not know the exact date an event occurred.
Circa
Because early humans relied on hunting animals and gathering wild plants to survive, historians call them by this collective name.
Hunter-Gatherers
Early humans crafted these long-range hunting weapons by attaching sharp stone tips to wooden shafts.
Spears
Natural formations like these served as early shelters for hunter-gatherers, protecting them from wind, rain, and predators.
Caves
Standing for "Common Era," this abbreviation is the modern, non-religious equivalent of AD.
CE
This time unit represents a span of exactly 10 years.
Decade
Early humans moved constantly from place to place following animal herds and seasonal crops, a lifestyle described by this word.
Nomads or Nomadic
Hunter-gatherers shaped tools and weapons primarily out of these three natural materials found in their environment.
Stone, bone, and/or wood
Because hunter-gatherers moved constantly, their handmade shelters had to be easy to take down, transport, and rebuild—making them this type of shelter.
Temporary Shelters
The Latin phrase Anno Domini, abbreviated as AD, translates to this English phrase.
In the year of the Lord
This time unit represents a span of exactly 100 years.
Century
Instead of living in large cities, early hunter-gatherers lived in these small, related social groups for safety and survival.
Tribes/Clans
Early humans flaked and chipped this hard, dark stone to create razor-sharp cutting edges for axes and knives.
Flint
Early humans constructed temporary tents using wooden poles or mammoth bones covered with this outer material.
Animal Skins (Hides/Furs)
If an event happened in 2500 BCE and another happened in 1000 BCE, this is the number of years that passed between them.
1,500 years
The year 330 BC/BCE belongs to this century
Fourth Century BC/BCE
In typical hunter-gatherer societies, this group was primarily responsible for gathering wild nuts, berries, roots, and plants.
Women
Used to clean animal hides for clothing, this flat stone tool was essential for hunter-gatherers living in cold climates.
Scraper
Besides providing warmth, fire allowed early humans to do this to their meat, which killed bacteria and made food easier to digest.
Cook it
Unlike modern years which count forward as time passes, dates labeled BC or BCE count in this direction on a timeline.
Backward or toward zero
If a textbook says an ancient village was built ca. or c. 4000 BCE, the author is communicating this about the date.
Estimate/Approximate Date (Guess). Circa
Hunter-gatherer groups were forced to pack up and move when this critical resource ran out in their immediate area.
Food or resources
Made from bone, early hunter-gatherers would use this tool to create clothing made from animal hides
Needle
Controlling fire gave nomadic bands a tactical advantage at night by doing this to dangerous animals.
Scaring them away/protection