This led to several symposia on the subject of vertebrate trace fossils. In 1986 such a conference dedicated to dinosaur footprints was held in New Mexico. Roughly a decade later renowned German ichnologist Heinrich Haubold organized a conference dedicated to the more ancient footprints of the Paleozoic Era. This gathering has been regarded as a turning point in the study of tracks of that age.  1900  1902  1903  1904  1905  1906  1908  1909  1910  1913  c. 1914  1914  1915  1915-1916  1918   c. 1920  1923  1924  1925  1926  1927  1928  1929   1931  1932  1933  1936  1937  1938  c. 1939  1939   1940  1941  1943  1944  1947  1948   1951  1952  1953  1954  1955  1957  1958  1959   1960  1962  1963  1965  1966  1967  1968  1969   1970  1971  1972  1973  1974  1975  1976  1977  1978  1979   1980  1981  1982  1983  1984  1985  1986  1987  1988  1989  1990  1991  1992  1993  1994  1995  1996  1997  1998